I doubt it had anything to do with ego as the blog suggests. Once things get to production there can be a managerial aversion to any change due to the amount of tracking/process involved. Someone probably got an ego boost from getting the fix into production in spite of the process by circumventing it. The big issue is not so much that they violated the part release process - which is bad, but that the severity of the issue did not get elevated to the point that it would cause a recall. This in spite of having some very fine safety analysis people.