I'd say League. Games may not start that way but they can end up that way pretty quickly. Like, people can play well in certain states. Once they get out of that state they may pay like shit. E.g get killed twice in quick succession and they start doubting themselves or playing to aggressive trying to catch back up and keeping making mistakes as a result.
Being able to keep a level head is as much a skill as anything else.
It does make me think how many people would describe a good player as a overly competitive player. It's completely subjective and up for interpretation