Sometimes a motivation trap takes the form of a fundamental cognitive malfunction, and the modified ego is unable to look after itself, much less undo its mod. The more feared traps are subtle, taking the form, as the name implies, of a shift in fundamental attitudes and motivations. The classic exhuman fable illustrating this is of a powerful exhuman who thought it would be valuable to temporarily be a series of different personalities. He altered himself into a devout Buddhist successfully, but while the exhuman had been interested in being a Buddhist, the Buddhist was no longer interested in being an exhuman, and never changed back.
For these reasons, it is standard practice among cautious exhumans to maintain and keep running a backup of its last stable version of itself. The backup oversees all experimentation and modification, testing the resulting modified thoroughly before accepting any changes into itself.
Plot Hook: Exhumans do a lot of dangerous experimentation; how often does a well-armed Firewall/Ozma team fight past the automated defenses of an exhuman brinker hab, only to find that its owner has managed to off itself? Firewall has tasked the players with tracking down an exhuman threat. When they breach its isolated hab, they find that it accidentally rendered itself catatonic months ago and starved to death; its progeny, however, are very much alive.