The Avengers are Marvel's answer to DC's Justice League, but oh, did Saban blow chunks trying to adapt the series to television for Fox in 1999. If you don't believe me, check out the opening.
I don't know who came up with the idea to cover the Wasp's pretty face with a retractable helmet-mask (they did the same thing with Ant-Man). I guess they figured, she's called the Wasp, so let's give her a bug-shaped mask to match. Morons. Fortunately, even though she was killed off in the comic books, Wasp has been, ah, "reincarnated" in the current Avengers series airing on DisneyXD (and reviewed over in The Land of Whatever), as gorgeous as ever. Unfortunately for this batch of Avengers, they never really had a chance to get going. Fox, obsessed with trying to derail the ratings express known as Pokemon over on Kids' WB!, delayed the debut of Avengers for a few weeks, then pulled it after a month when it finally aired.
Saban didn't try to screw up the X-Men, so why mess with other Marvel icons? I don't think that will ever be answered.