A consistant pattern with many DAAs is that they over-stretch their own abilities. They go for too much too soon and they get caught easily. Their margin for error is too small.
Examine Dylan Roof’s actions. He went from internet racist to killing 6 blacks inside of a church. That action was about as hot as a multiple homicide can get in Murka. He might have begun with just one person and learned from the experience.
One can see this clearly in Ander’s manifesto. By the time for the event, he was mentally, physically and emotionally exhausted. He didn’t want to get away with it. In a way, prison is a vacation for him, a rest.
The equivalent situation is a gambler who over-bets his bankroll. This causes one to underestimate the standard deviation, and often leads to losing it all.