It might have had to bypass some of the more stringent parts of Boeing's development process to avoid appearing in documentation that the customer or the FAA might see.
If so, it amounts to criminal negligence. People should go to jail, but if anybody does, it will certainly not be the ones ultimately responsible. Most likely Boeing will pay fines and court judgments, something probably already factored into their stock price, impacting people holding the stock this year, not those who might have demanded better management five years ago.
Certainly the whole top tier of management should be fired, but that won't happen either.
The failures were first political, second managerial, and third ethical. The actual engineering failure is a far fourth.