There was a great interview Ryan did a few months back about xmen origins. Basically, they wanted to do the movie and wanted Ryan as deadpool. They asked him and he basically signed on the spot. Except then the writers strike happened. And of course because studios are all about the bottom line, the set a release date without even having a script. Half that movie was made A WITHOUT AN ACTUAL SCRIPT. All of a sudden, everything makes sense. The "wade Wilson" part was done without any dialogue written. They just told the cast to say stuff. So anyways, they get the script finally written, call Ryan up to film "The Deadpool" and he's like, uh... People are going to be really upset with what you want to do. But they did it anyways. Due to "scheduling conflicts" they got Scott Adkins to play barakapool and after early screenings they called up Ryan and were like, OKAY THEY REALLY DON'T LIKE WHAT WE DID HALP!
That's why they had that super lame after credit scene with deadpool's head. They promised Ryan a deadpool movie if he helped them out with that scene.
So, I think that already know how badly they screwed up