Has anybody ever been out, say in a restaurant or at someone's house, and you feel like you really need to pass quite a lot of gas, so you go to the bathroom for the privacy and sit on the toilet for a while and suddenly feel that now you're in the right place the gas won't come? You wait a while but to no avail, but as soon as you return to the social setting the gas immediately wants to come again?
This is one of the most annoying and unpleasant things that can happen in company, especially when you're the sort who is shy of farting in front of people or in public.
It's like your bowels are playing mind games with you.