There’s only one step from win to disqualification.
But in the heat of the brawl an unexperienced fighter can forget even that. This video from “Strelka” taken in August, 2014, is a good example (skip to 0:50 to get to the fight instantly). We have two guys, both of them seem new to fighting: the distance they try to keep is way too long and the strikes and kicks are somewhat clumsy and inaccurate. At the time mark of 2:14 the blond guy whose nickname is “Skeleton” lands a solid kick to the body followed by the arm triangle choke attempt. The rocked opponent falls down and suffers a devastating kick to the head which puts him to sleep.
The first thought here is like “what the #### was he thinking anyway?” But as you watch how “Skeleton” grabs his head in despair, you realize he did it not because he is a badass but of a mere overexcitement and lack of experience. Things like that rarely happen in pro tournaments, though Badr Hari and Remy Bonjasky could argue with that after their clash at K-1 Grand Prix Yokohama