The Greens ran their biggest ever federal campaign this election and received more media attention than before yet failed to capitalise on disenchantment with the major parties. As party strategists analyse the results, will they correctly diagnose what went wrong or descend into a bout of finger-pointing and internal blame games?

In 2013 the Greens won the seat of Melbourne without Liberal preferences for the first time and expanded their numbers in the Senate to 10, a new record. Despite their increased parliamentary presence, party leader Christine Milne declared the result a disappointment, because of a national primary vote swing against the Greens, and became the target of substantial internal pressure.

This weekend the Greens failed to make gains in the lower house and have lost at least one senator. It’s the first time the party has gone backwards in terms of parliamentary representation since 1998, yet publicly its leadership seems upbeat. The difference in post-election reaction between 2013 and now is partly due to a wildly variable result in different parts of the country, skilful media management and an internal culture that doesn’t easily allow for open and frank critique.

This election, in the House of Representatives, the Greens recovered slightly from their poor 2013 vote, receiving 9.9% of national vote – a swing of 1.3%. This result is still 2% worse than what the party achieved in 2010. The Greens poured resources into targeted seats across NSW and Victoria, hoping to add to their lower house numbers. In inner-city Melbourne seats like Batman and Wills, the party achieved big swings of up to 9%, but failed to win. In the Sydney seat of Grayndler, the Greens’ best chance of winning a seat in NSW, the vote went backwards and in the seat of Sydney it stayed flat.

Greens campaigners are still trying to come to terms with the hugely variable result across Victoria and NSW, though some party figures have already started blaming the NSW branch’s lack of “professionalism”. Greens strategists in NSW argue that in Victoria the party was up against incumbent Labor MPs from the party’s right faction, including David Feeney who became the subject of ridicule for his gaffe-prone campaign, while in NSW the Greens’ targets were the much tougher, popular leftwing Labor MPs Tanya Plibersek and Anthony Albanese.

Nevertheless, the NSW Greens spent up big in Grayndler, Sydney and the north coast seat of Richmond, devoting nearly one third of the party’s statewide campaign budget to winning those seats. The failure to even come close has already sparked soul-searching, with the NSW party assessing its approach to the campaign and questioning whether the lower house was over-prioritised compared with the Senate.

In the Senate the Greens performed poorly. On current figures the party is on track for its worst Senate result since 2004. The party has already lost a Senate seat in South Australia and there is a chance the party could lose two additional senators, in Tasmania and Western Australia where the Greens saw swings against them. In South Australia the Greens have blamed Nick Xenophon for their worst result in 15 years. But given Nick Xenophon went backwards in the Senate, along with the Greens, there are clearly other factors at play. The party will need to identify what it is doing wrong in South Australia, and how to neutralise the Xenophon factor, or it risks losing its sole remaining senator at the next election.

The Greens started this election campaign buoyant about their chances of breaking into additional lower house seats. Party leader Richard Di Natale kicked off his campaign in Grayndler, signifying how seriously the party was taking the seat.

When the Liberal party announced it would preference Labor ahead of the Greens, dealing a significant blow to the minor party’s chances of winning, Di Natale shifted his rhetoric and claimed that if the Greens didn’t win targeted seats this election they would win them next election.

The clear lesson from this election is that there is nothing inevitable about the party’s trajectory. Despite spending more money than ever and running a massive volunteer effort, the party did not make any inroads in inner-city Sydney. In Melbourne the party came close, but if they could not defeat Feeney after he ran probably the worst campaign in the country, it’s not clear why they would somehow win next election. And unless it dramatically increases its vote, more Senate seats could be lost at the next election.

Some long-term Greens campaigners have begun to question the party’s more moderate political direction under Di Natale. Christine Cunningham, the national co-convenor of the Australian Greens in 2013 and 2014, said: “In a world desperate for change and hope, we offered a centrist position summed up in a vague slogan.

“We can continue to be led by a nice-guy, mainstream footy-playing doctor and negotiate incremental change ... Or maybe as a party of really smart, but often too-privileged-to-quite-get-it members, we should take a long hard look at ourselves and make some radical changes.”

Cunningham’s comments are significant because it’s incredibly rare for senior party figures to speak on the record about the Greens’ internal political tensions. The party often feels under siege from media attacks and, unlike in the major parties, public, on the record introspection after poor election results is almost never heard of. Cunningham said it was important to speak up because “we will never move from the 10% plateau unless we do a deep analysis of why we are stuck here”.

Di Natale is regularly described as a leader who shifted the Greens towards a more “mainstream”, moderate position. The truth is the party has long been on a trajectory that prioritises parliamentary deal-making. In 2010 the party was able to secure significant policy wins through this approach, though they were punished at the ballot box in 2013 and weren’t able to recover this election.

The problem the Greens face is that they have pursued a “steady as she goes” approach over the past decade while the Australian public has been simultaneously losing its faith in politics and rejecting the whole concept of political stability and business as usual. This is why the party has been unable to capitalise on voter distrust with the political establishment in the same way as Nick Xenophon and other minor parties and independents. They have spent the last few terms of parliament trying to become the political establishment while voters have spent every election since 2007 punishing whoever is in power.

But despite their failure to capitalise this time around, the Greens are still a significant political force. They may play a lesser role in parliament, but given the public mood that could turn out to be a good thing electorally. The biggest mistake the party could make right now would be to bury its head in the sand and pretend this result was a success. The party has the technical and political ability to position itself as a real political force, tapping into disenfranchised voter sentiment and shaping it, but it needs to re-evaluate and radically overhaul its current approach to pull it off.