I don't even think I've asked 250 questions in the entire several years I've been here, let alone one day! :)
I guess a limit sounds "limiting," though. Yet, 250 sounds like a good limit and enough for one day. About ten questions an hour if one were to be at the site for 24 hours. Or 250 in one hour and then go lie down. :)
I am always for Quality instead of Quantity. When I ask a question I try to find one which is engaging and leads to opinion exchanges and longer threads. And I stay with it to be present when the answers pour in. I love good conversations. How could I find time for more then without neglecting my daily chores. I like to laugh and have fun also......Official limits are not recommendable, but trying to crash the site with questions is senseless and useless.