I think it is only boxing that does this but not sure. I only learned boxing did it a few days ago when a Canadian fighter won his quarterfinal match and the announcer said "and that will guarantee him a medal". At first I thought he had gotten overzealous and made a mistake but later in the broadcast they explained how it worked. 

I hate that. Do any of the tournament style competitions have bronze medal games?

I thought there was a different method of assigning 3rd place in competitions like that.

Undisciplined

“The rule was introduced due to the short interval between the semi-final and the third-place match. The boxers did not get adequate time to recover, which risked their health.”

grayruby

Stacker_Sports

Stacker Sports- Saturday Poll

Did you know they give an extra bronze in boxing events? There is no bronze medal fight. The two losers of the semifinals get bronze and the winners fight for gold. So that would throw off your math a bit. 