When Does a Hobby Start Taking Up Too Much Space?

Has anyone else noticed how easy it is to lose track of time when doing something that's supposed to be just a bit of entertainment? Last weekend I planned to spend half an hour watching a match and checking a few odds, but somehow the evening disappeared. Nothing dramatic happened, but it made me wonder how people actually keep their hobbies from interfering with everyday routines. Do you set strict time limits, use reminders, or simply rely on self-discipline? I'm curious whether these little boundaries genuinely work in practice or whether most people only start thinking about them after something goes wrong.