I know this thread is a few months old, but I wasn't very active for a while and wanted to add a little to this thread.
One of the most comical finishers I ever seen was the Tornado Punch by, The Texas Tornado Kerry Von Eric. I mean, it went with his gimmick but it looked like a cartoon in the ring. More or less, it appeared as if it were to be meant for the entertainment of children. Such a sloppy finisher for a former World Champion. RIP
The Ultimate Warrior's splash was also horrible. What makes matter worse is that he was the first guy to defeat Hogan Clean... and he used this move! I mean crap, Hogan could kick out of Andre splashing him, but a 150 LB guy with less force than a 70 year old grandma can keep you down for three!? Give me a break!
The Great Khali's chop is also horrendous. If he used more speed to it, I would buy into it more. But that little bit of force, without the speed, doesn't knock a man out.
Anyone remember Bastion Booger? Of course not... Anyway, this morbidly obese gentlemen would sit on his opponents and pin them. What was this move called you ask? "A trip to the Batcave"....
So there are a few from me, that were not already mentioned in this thread. Some of you guys had already posted a few I agree with, so I didn't include them in my post.