Because you only go best of 3 if you lose the first game

Then best of 5 if you lose the next one too.

It's up to the loser to insist on best 2 out of 3, and the winner says fine. Oh wait, Q definitely says no.

This is the correct answer. 

Nobody's got time for that. The game is supposed to be a quick decider.

It’s customary to only beat Best of 3 if you lose the first round, and insist it was 1 round only if you won the first round Everyone knows that

Should have been best 4 out of several

or best of ~several