#6 Sid forgets that he's on live television
(Couldn't find a video of this one on its own. Luckily, it's the first one on this Top 10 that WWE made)
Sid looked like the perfect archetype of a professional wrestler - he was a nearly seven foot tall, over a 300-pound wall of muscle. He likely would've been a lot bigger of a deal back then...if he could only string a sentence together.
Simply put, Sid was pretty awful on the microphone. Granted, the man probably never took an acting class in his entire life, but his ineptitude gave us some pretty excellent promo bloopers. For example, before his WWF championship match with Diesel at In Your House, he stumbled on the word "sceptics" and tried to get them to shoot the promo again...even though it was a live interview.
Somewhat kayfabe-shattering, yes, but hilarious nonetheless.