I'm just using both as examples of guys that used more than one finisher, I could be here all day naming every superstar that has more than one finisher, but I just picked a couple of the more well known ones off the top of my head. apologies if it seemed that I was comparing Ryback to those guys.
The fact that Batista or Taker could hit their finishers on all opponents is irrelevant. The fact is Ryback can't (or supposedly can't), and if you think that that is going to stop his push, then that's not the case IMO, it's just a case of him using a different finisher. And by that I don't mean necessarily adding another finisher, but just changing his current one.