We're all here to have fun. It's not fun for the DM if you ruin the game, it's not fun for the players if you LULSORANDOM them, it's not fun for you if the DM arbitrarily ruins your character.
This seems to get most of the bases covered. Anything more specific than that will be up to whomever is running the game since we rotate DMs to prevent burnout, but all of us work from that basic agreement.