In almost every example of this I can come up with, amnesiac characters almost always becomes opposed to whatever they were doing before they lost their memory. I think it's a nice symbol for how we all have deep regrets, and chore-y things we do because we have to (e.g. being stuck in a job we hate because it's a reliable source of being able to eat). Losing all your memories means you get to start from a blank slate, free of all that.