(CNN) It was heralded as a breakthrough in the mystery of the missing jet.

Malaysia's Prime Minister appeared before television cameras to say investigators had conclusively determined that aircraft debris found on an island in the Indian Ocean came from Malaysia Airlines Flight 370, which vanished on March 8, 2014, with 239 people aboard.

Prime Minister Najib Razak did not equivocate: "It is with a heavy heart that I must tell you that an international team of experts have conclusively confirmed that the aircraft debris found on Reunion Island is indeed from MH370."

The search for the plane is an international effort, but Najib, as the leader of the country where the flight originated, should be a source as informed as anyone.

So, why have some of the victims' families reacted with skepticism, and even anger, at the Malaysian announcement? One key reason is that Malaysia has made several missteps in handling the disappearance of MH370.

JUST WATCHED MH370 family reaction: I don't believe it, I am furious Replay More Videos ... MUST WATCH MH370 family reaction: I don't believe it, I am furious 02:20

The misfires include an impersonal text to relatives of people aboard to say that no one survived -- and saying days later that some people may have survived after all. They also include a failure to immediately detect radar clues. Malaysian authorities also announced the final words heard from the cockpit, only to say later that the pilot or co-pilot said something slightly different.

That helps explain why some relatives of MH370 passengers have reacted with skepticism to the Malaysian Prime Minister's definitive assertion, a suspicion that was only bolstered when a French prosecutor, who actually examined the piece of debris in question, used slightly less conclusive language; he said that the part probably came from MH370 but that more tests were needed to say so with absolute certainty.

"I don't believe it," one family member told CNN. "This announcement is very irresponsible."

Analyst: Latest news is suspect

The families have every right to be skeptical, said CNN safety analyst David Soucie. Even with Thursday's government announcement that a window and seat cushion are believed to be part of Malaysia Airlines Flight 370, Soucie said he found the news "suspect," in part, because none of the hundreds of people involved in the search found anything until the Malaysians arrived.

"All of the debris studies show rapid and extensive debris disbursement projections," he said in an email. "Could debris of such diverse size, weight and buoyancy end up on the same small island at the same time? Doubtful."

Photos: The search for MH370 Photos: The search for MH370 Two years after Malaysia Airlines Flight 370 went missing, a relative of one of the passengers burns incense in Beijing on March 8, 2016. Flight 370 vanished on March 8, 2014, as it flew from Kuala Lumpur, Malaysia, to Beijing. There were 239 people on board. Hide Caption 1 of 43 Photos: The search for MH370 On July 29, police carry a piece of debris on Reunion Island, a French territory in the Indian Ocean. A week later, authorities confirmed that the debris was from the missing flight. Hide Caption 2 of 43 Photos: The search for MH370 Staff members with the Australian Transport Safety Bureau examine a piece of aircraft debris at their laboratory in Canberra, Australia, on July 20. The flap was found in June by residents on Pemba Island off the coast of Tanzania, and officials had said it was highly likely to have come from Flight 370. Experts at the Australian Transport Safety Bureau, which is heading up the search for the plane, confirmed that the part was indeed from the missing aircraft. Hide Caption 3 of 43 Photos: The search for MH370 In late February, American tourist Blaine Gibson found a piece of plane debris off Mozambique, a discovery that renewed hope of solving the mystery of the missing flight. The piece measured 35 inches by 22 inches. A U.S. official said it was likely the wreckage came from a Boeing 777, which MH370 was. Hide Caption 4 of 43 Photos: The search for MH370 Relatives of the flight's passengers console each other outside the Malaysia Airlines office in Subang, Malaysia, on February 12, 2015. Protesters had demanded that the airline withdraw the statement that all 239 people aboard the plane were dead. Hide Caption 5 of 43 Photos: The search for MH370 A police officer watches a couple cry outside the airline's office building in Beijing after officials refused to meet with them on June 11, 2014. The couple's son was on the plane. Hide Caption 6 of 43 Photos: The search for MH370 Members of the media scramble to speak with Azharuddin Abdul Rahman, director general of Malaysia's Civil Aviation Department, at a hotel in Kuala Lumpur, Malaysia, on May 27, 2014. Data from communications between satellites and the missing flight was released the day before, more than two months after relatives of passengers said they requested it be made public. Hide Caption 7 of 43 Photos: The search for MH370 Operators aboard the Australian ship Ocean Shield move Bluefin-21, the U.S. Navy's autonomous underwater vehicle, into position to search for the jet on April 14, 2014. Hide Caption 8 of 43 Photos: The search for MH370 A member of the Royal New Zealand Air Force looks out of a window while searching for debris off the coast of western Australia on April 13, 2014. Hide Caption 9 of 43 Photos: The search for MH370 The HMS Echo, a vessel with the British Roya; Navy, moves through the waters of the southern Indian Ocean on April 12, 2014. Hide Caption 10 of 43 Photos: The search for MH370 A Royal Australian Air Force AP-3C Orion, on a mission to drop sonar buoys to assist in the search, flies past the Australian vessel Ocean Shield on April 9, 2014. Hide Caption 11 of 43 Photos: The search for MH370 A relative of a missing passenger cries at a vigil in Beijing on April 8, 2014. Hide Caption 12 of 43 Photos: The search for MH370 Australian Defense Force divers scan the water for debris in the southern Indian Ocean on April 7, 2014. Hide Caption 13 of 43 Photos: The search for MH370 A towed pinger locator is readied to be deployed off the deck of the Australian vessel Ocean Shield on April 7, 2014. Hide Caption 14 of 43 Photos: The search for MH370 A member of the Royal New Zealand Air Force looks at a flare in the Indian Ocean during search operations on April 4, 2014. Hide Caption 15 of 43 Photos: The search for MH370 On March 30, 2014, a woman in Kuala Lumpur prepares for an event in honor of those aboard Flight 370. Hide Caption 16 of 43 Photos: The search for MH370 The sole representative for the families of Flight 370 passengers leaves a conference at a Beijing hotel on March 28, 2014, after other relatives left en masse to protest the Malaysian government's response to their questions. Hide Caption 17 of 43 Photos: The search for MH370 A member of the Royal Australian Air Force is silhouetted against the southern Indian Ocean during the search for the missing jet on March 27, 2014. Hide Caption 18 of 43 Photos: The search for MH370 Flight Lt. Jayson Nichols looks at a map aboard a Royal Australian Air Force aircraft during a search on March 27, 2014. Hide Caption 19 of 43 Photos: The search for MH370 People in Kuala Lumpur light candles during a ceremony held for the missing flight's passengers on March 27, 2014. Hide Caption 20 of 43 Photos: The search for MH370 Malaysian Prime Minister Najib Razak, center, delivers a statement about the flight on March 24, 2014. Razak's announcement came after the airline sent a text message to relatives saying it "deeply regrets that we have to assume beyond any reasonable doubt that MH 370 has been lost and that none of those onboard survived." Hide Caption 21 of 43 Photos: The search for MH370 Grieving relatives of missing passengers leave a hotel in Beijing on March 24, 2014. Hide Caption 22 of 43 Photos: The search for MH370 A passenger views a weather map in the departures terminal of Kuala Lumpur International Airport on March 22, 2014. Hide Caption 23 of 43 Photos: The search for MH370 A Chinese satellite captured this image, released on March 22, 2014, of a floating object in the Indian Ocean, according to China's State Administration of Science. It was a possible lead in the search for the missing plane. Surveillance planes were looking for two objects spotted by satellite imagery in remote, treacherous waters more than 1,400 miles from the west coast of Australia. Hide Caption 24 of 43 Photos: The search for MH370 Satellite imagery provided by the Australian Maritime Safety Authority on March 20, 2014, showed debris in the southern Indian Ocean that could have been from Flight 370. The announcement by Australian officials raised hopes of a breakthrough in the frustrating search. Hide Caption 25 of 43 Photos: The search for MH370 Another satellite shot provided by the Australian Maritime Safety Authority shows possible debris from the flight. Hide Caption 26 of 43 Photos: The search for MH370 A distraught relative of a missing passenger breaks down while talking to reporters at Kuala Lumpur International Airport on March 19, 2014. Hide Caption 27 of 43 Photos: The search for MH370 On March 18, 2014, a relative of a missing passenger tells reporters in Beijing about a hunger strike to protest authorities' handling of information about the missing jet. Hide Caption 28 of 43 Photos: The search for MH370 U.S. Navy crew members assist in search-and-rescue operations in the Indian Ocean on March 16, 2014. Hide Caption 29 of 43 Photos: The search for MH370 Members of the Chinese navy continue search operations on March 13, 2014. After starting in the sea between Malaysia and Vietnam, the plane's last confirmed location, search efforts expanded west into the Indian Ocean. Hide Caption 30 of 43 Photos: The search for MH370 A Vietnamese military official looks out an aircraft window during search operations March 13, 2014. Hide Caption 31 of 43 Photos: The search for MH370 Malaysian air force members look for debris near Kuala Lumpur on March 13, 2014. Hide Caption 32 of 43 Photos: The search for MH370 Relatives of missing passengers wait for the latest news at a hotel in Beijing on March 12, 2014. Hide Caption 33 of 43 Photos: The search for MH370 A member of the Vietnamese air force checks a map while searching for the missing plane on March 11, 2014. Hide Caption 34 of 43 Photos: The search for MH370 A Vietnamese air force plane found traces of oil that authorities had suspected to be from the missing Malaysia Airlines plane, the Vietnamese government online newspaper reported on March 8, 2014. However, a sample from the slick showed it was bunker oil, typically used to power large cargo ships, Malaysia's state news agency, Bernama, reported on March 10, 2014. Hide Caption 35 of 43 Photos: The search for MH370 A U.S. Navy Seahawk helicopter lands aboard the USS Pinckney to change crews on March 9, 2014, before returning to search for the missing plane in the Gulf of Thailand. Hide Caption 36 of 43 Photos: The search for MH370 Buddhist monks at Kuala Lumpur International Airport offer a special prayer for the missing passengers on March 9, 2014. Hide Caption 37 of 43 Photos: The search for MH370 Members of a Chinese emergency response team board a rescue vessel at the port of Sanya in China's Hainan province on March 9, 2014. Hide Caption 38 of 43 Photos: The search for MH370 The rescue vessel sets out from Sanya in the South China Sea on March 9, 2014. Hide Caption 39 of 43 Photos: The search for MH370 Malaysian Prime Minister Najib Razak, center, arrives to meet family members of missing passengers at the reception center at Kuala Lumpur International Airport on March 8, 2014. Hide Caption 40 of 43 Photos: The search for MH370 A relative of two missing passengers reacts at their home in Kuala Lumpur on March 8, 2014. Hide Caption 41 of 43 Photos: The search for MH370 Chinese police at the Beijing airport stand beside the arrival board showing delayed Flight 370 in red on March 8, 2014. Hide Caption 42 of 43 Photos: The search for MH370 Malaysia Airlines Group CEO Ahmad Juahari Yahya, front, speaks during a news conference at a hotel in Sepang on March 8, 2014. "We deeply regret that we have lost all contacts" with the jet, he said. Hide Caption 43 of 43

The Malaysian government has certainly been wrong before when it comes to the hunt for Flight 370.

In an opinion piece critical of the Malaysian government, CNN aviation analyst Les Abend questioned whether it had learned its lesson from past missteps.

"Because of the difficulty in processing such a catastrophic event like an aircraft accident, rational thought often goes out the window," he wrote. "If a history of misinformation has been established, this only adds to the trauma. Mistrust and anger become natural parts of the emotional reaction. This is normal."

He further offered advice on how the governments involved in the search could get their acts together: "Communicate the facts only. And if this means withholding information from the media for a period of time, so be it."

The doubts only deepened after the French team inspecting the debris said more tests are being done to be completely certain.

Another family member said: "The families want 100% confirmation. ... That means Boeing company and the French investigators. We don't want 99%. Malaysian authorities have been trying to force a closure ... for themselves, not for the families."

What missteps have Malaysian authorities made since MH370 disappeared? Critics have highlighted several in their early response.

Accusations of errors, incompetence

Malaysian military radar captured signatures of what was believed to have been Flight 370, but they weren't immediately noticed.

JUST WATCHED From disappearance to debris: CNN's coverage of MH370 Replay More Videos ... MUST WATCH From disappearance to debris: CNN's coverage of MH370 03:16

While the radar data was the key reason for expanding the search west of Malaysia, it took officials until March 11 -- three days after the disappearance -- to explain why they were looking so far off the plane's expected course. All the while, search efforts continued in places where data showed it could not have been -- the Gulf of Thailand and the South China Sea.

A report issued a month after the plane's disappearance also highlighted snafus in crucial communication between air traffic control centers and Malaysia Airlines on the morning Flight 370 disappeared.

These kept officials from realizing the airplane had gone hundreds of miles off course for several hours and delayed attempts to find it.

Failure to share information

China and some U.S. officials expressed frustration over what they said was Malaysia's initial failure to share information or accept more offers of help.

"Time is life," said a Chinese Foreign Ministry statement, eight days after the plane's disappearance.

The lack of concrete information created plenty of space for speculation and conspiracy theories to run rife. Was the plane hijacked? Could terrorism have been involved? Was the plane in fact brought down somewhere on land?

Relatives told 'no survivors' by text message

Malaysia Airlines and the Malaysian government incurred the wrath of many relatives when, 16 days after the disappearance, victims' family members received a text message telling them that the plane was believed to be lost in the southern Indian Ocean "and that none of those on board survived."

Photos: Remembering the passengers of MH370 Photos: Remembering the passengers of MH370 There is still no way to know for sure why Flight MH370 ended, but we are learning more about the lives of those on board. CNN is remembering them through snapshots shared with us. Hide Caption 1 of 12 Photos: Remembering the passengers of MH370 Rodney and Mary Burrows were looking forward to becoming first-time grandparents after their return home to Australia. Hide Caption 2 of 12 Photos: Remembering the passengers of MH370 Australians Catherine and Robert Lawton were traveling with friends on vacation when the flight disappeared. Hide Caption 3 of 12 Photos: Remembering the passengers of MH370 Paul Weeks was traveling to Mongolia for a new job as an engineer. His wife says Paul left behind his watch and his wedding ring before the trip, in case anything happened to him while he was away. Anderson spoke with Paul's brother & sister who said they are coping by spending time together as a family. Hide Caption 4 of 12 Photos: Remembering the passengers of MH370 Chandrika Sharma, left, was on Flight 370; her daughter Meghna and husband K.S. Narendran wait patiently, trying to manage their anxiety and longing for her return. Hide Caption 5 of 12 Photos: Remembering the passengers of MH370 Muktesh Mukherjee and Xiaomo Bai had been vacationing in Vietnam and were on their way home to their two young sons in Beijing. Hide Caption 6 of 12 Photos: Remembering the passengers of MH370 76-year-old Liu Rusheng, an accomplished calligrapher and one of the oldest passengers on the flight, was in Malaysia to attend an art exhibition with his wife. Hide Caption 7 of 12 Photos: Remembering the passengers of MH370 Teens Hadrien Wattrelos and Zhao Yan are shown in a photo on Wattrelos' Facebook page. The photo is captioned, simply, "I love you," in French. Hide Caption 8 of 12 Photos: Remembering the passengers of MH370 Firman Chandra Siregar, 24, studied electrical engineering in Indonesia and was on his way to Beijing on board Flight 370 to start a new job at an oil company. Hide Caption 9 of 12 Photos: Remembering the passengers of MH370 Patrick Francis Gomes, center, was the in-flight supervisor for the missing plane. His daughter describes him as a quiet person with a sense of humor. Hide Caption 10 of 12 Photos: Remembering the passengers of MH370 Ch'ng Mei Ling, a Malaysian citizen who lives in Pennsylvania, is a process engineer at a chemical company. Hide Caption 11 of 12 Photos: Remembering the passengers of MH370 We do not have photos of all 239 passengers, but we wanted to remember that there are loved ones around the world missing them right now. View CNN's complete coverage of Flight 370. Hide Caption 12 of 12

The airline defended its approach, saying it was keen to make sure that the families heard the news before it was shared with the rest of the world by the Malaysian Prime Minister.

But relatives said a text message was no way to convey such terrible news.

Then, within days -- after family members had angrily blasted the conclusion as premature and lacking hard evidence -- acting Minister of Transport Hishammuddin Hussein told reporters that he had not entirely given up hope of finding survivors.

"Even hoping against hope, no matter how remote, of course, we are praying and we will continue our search for the possible survivors," he said.

Error over last words from cockpit

People's trust was also undermined by other inconsistencies in what the government said.

On March 17, Malaysian authorities publicly confirmed the final words from the cockpit as "All right, good night."

The innocuous bit of radio banter became yet another headache for investigators when, after days of prodding from reporters and family members, they released a transcript showing the final words were actually, "Good night Malaysian three seven zero."

It's not that the new language was suspect -- it's not. It's that Malaysian officials got the original wording wrong, let it stand for nearly two weeks, and then -- after saying they wouldn't release the transcript because of its role in the investigation -- suddenly reversed course.

Officials also wavered over whether the words were spoken by co-pilot Fariq Abdul Hamid or pilot Zaharie Ahmad Shah, before finally saying it was the latter.

Doubts over evidence, transparency

From the beginning, the families of those missing complained of a lack of information and transparency from the Malaysian government and Malaysia Airlines.

Early briefings were chaotic, leading some to question who was in charge. Angry relatives accused authorities of deliberate search delays and coverups.

In the first hours after the plane disappeared from radar screens, not long after it left Kuala Lumpur's international airport, the Malaysian government acknowledged that it had no idea where it had gone.

Relatives slammed the airline's updates as infrequent and its support as inadequate, including an offer of $5,000 immediate financial assistance to each family member.