For me, I like the rounds to hit somewhere within the area that my front sight is covering, when shooting for accuracy (slow fire) (So, what im aiming at)
At 5 yds this is about an inch
10 yds, maybe 2"
30 yds, ideally 6" but more realistically 8" for me.
Depends on the gun.
Revolvers w/6" barrels maybe a bit better
CCW w/ 3" barrel, a bit worse.
Ive heard of people who can shoot 2" groups at 35 yds off hand, but ive never actually seen it in person. Ive really learned to ignore what others say on this topic, because lots of times its grossly exaggerated, and it doesnt matter to me anyways. If i were to actually really see or meet someone who can shoot a hell of a lot better than me, then id be inspired.
If i fire 10 rounds and create an 8" group at 25 yds, often there are 3 or 4 or 5 shots in a 4" group, but i could care less... Cut my 4" Quasi-group in half again and take away my support hand, take away my 6" 586 and give me a GI mil spec 1911 .45 and then Id be keeping up with the Internet Rangers.