Apple is pushing hard to make its phones more secure, but the quest for perfect security will never be met.

"Getting to unbreakable is impossible," Apple engineers told CNNMoney, though there had been reports that the company was reportedly working toward that goal.

The engineers said that the company is constantly improving its security as hackers get more sophisticated, but that no company writes perfect code without some vulnerabilities.

That's one reason the company fought so hard against the government's request to create special software that would help them access the iPhone used by the San Bernardino terrorist -- a move that Apple said would ultimately weaken security.

The FBI ultimately was able to access that phone without Apple's assistance. But it has not disclosed the method or who helped do it.

Apple engineers think the government should share what they've learned.

"We would love to know what this mechanism is so that we could address it and fix it in our product... it goes without saying normal practices are to let the manufacturer know so it's fixed for all the customers," said the Apple engineer.

The Department of Justice declined to comment.

According to a former national security official at the DOJ, D.J. Rosenthal, there's a review process created by the White House to discuss providing information on the vulnerability to the manufacturer, in this case Apple.

"The basic presumption is that the government is going to share the exploits with companies, [but] given Apple's refusal to cooperate with the government, there's a strong interest on the other side not to share the information," he told CNNMoney.

Apple noted the government's success in this most recent case should not undermine customers' faith in the company's products. San Bernardino shooter Syed Farook was using an old -- and less secure -- version of the iPhone and operating system, they say. And law enforcement needed to be in possession of the iPhone to access it.

When asked how the relationship between Apple and law enforcement will play out as security gets better, the engineers suggested a broader discussion on FBI resources, budget, and acquiring talent.

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Additional reporting by Jose Pagliery