Lots of people here seem very upset at the idea that someone could write their memoires at thirty. While it wouldn't be something for me (either to do or to read), I can think of lots of reasons for doing it which would not have to be indicative of a disordered personality.

Maybe the author is just the kind of person who parses experience through the lens of writing. Writing down notes about what you're doing, what you feel about it, is could be a way of understanding it more richly. And there ARE advantages to records made in the moment. Yes, the author could wait until they're fifty and have achieved 'wisdom' or 'success' whatever the hell either of those things mean, before they look back on their life. But the record they'd come up with would be edited and distorted in so many ways that it would be useless as a description of how this person felt in their twenties.

Sure there's a chance that such a record will be self-indulgent, stupid, vacuous etc. But there's also a chance that writing of this kind will be one of the things which helps the author to grow. And even if doesn't, so what?