What did medieval European knights do if they were defeated in battle?

Question

I know that in medieval Japan, if samurai were defeated in battle or dishonored in any way they had to commit seppuku (killed themselves). I just wanted to know if medieval Europe had a similar rule.

Answer 1

No. This was not a military tradition in any European country. Although it as fairly common for a lord to execute their vassals for cowardice on the battlefield, it was not a codified practice.