When you have the option to bang someone and you have nothing better to do and can't think of a good reason not to so you go ahead.
In programming,

If not_to_bang_reason == NONE :

Return bang!
Person#1: I was there and so was he so I tossed him a "why not" bang.
Person#2: *shrug* why not!
Person#1: precisely.
by MissPoopyButthole June 21, 2019
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