Well, it depends. The reason this happens to me so much is that I try to do something new every time I jam. This time, for instance, I leaned heavily into Unity editor code. Made some graph tools and whatnot to build our maps. Eventually turned out that we only had one map because time, so that was all a bit of a waste of time, but the point is: lots of really occult problems. Mostly to do with serialization. But now, a week and a lot of refactoring later, I learned a LOT about that topic and understand where those occult problems originated from. Sure, it made our game worse (sorry team lol), but it's certainly a more entertaining way of learning than just getting out some dusty tome :)