They claim that the average dikk is 5.5 inches long and like 5 inches in circumference. Yet if you pull that out the average woman will laugh in your face. I wouldn't put too much weight into averages. And even if that is true its because most men don't care to try and go for hours. They just want a pump and done. Doesn't mean they can't train themselves to go all night.
Its all about being in tune with your body. Lasting for hours is not hard. It gets tedious after a while but its still possible. I always go for at least an hour. After that i usually cum and then go a couple more 30 minute rounds. i have gone 8+ hours I kept having to stop to make sure i didn't nut on myself. But i was able to last from when i got to the females house at 10am till well into the afternoon. when i finally pulled out and came i swear it flew past her head. Up my chest. everywhere and in every direction. Would do it again. But yea going 4 hours (the average all nighter) aint shyt. Especially if you're in shape and the bytch got joints.