I never used to flush the toilet until I was completely finished. Then, later on in life, I realized how rude this was. To stinkify the air that way. So I adopted the policy of timing the first flush so that the shit was immediately flushed away as soon as it hit the water. Of course, additional flushes were required for any more crap that was produced. Then more flushes for the toilet paper that came next. Overall, I flush at least 3 times for every crap but sometimes as many as 5.
I flushed immediately so as not to stink up the restroom.