Kane was slated to be a short-term character

During his podcast, The Undertaker revealed what was originally planned for the Kane character in WWE…

“Early on, they were just bringing him in for an opponent for me to beat. This was going to be a short-term deal. They had no idea they had no idea this was going to be what it turned out to be. They were bringing him in to be win for me and it turned into something just a little bit bigger.”

“Obviously, he comes in, in this incredible shape. Like, you know, because he had had a couple other opportunity — I don’t even know if you can call those opportunities. They kind of pigeon-holed him in some bad [gimmicks] you know fake Diesel and Isaac Yankem. I mean, that is not … that’s not doing anybody any favors.”

(quotes: WrestlingInc.com)