#4 To give Rey Mysterio a big win
If a title match was supposed to happen, in all likelihood, Samoa Joe would have picked up a win. Considering how poorly he's been booked over the past few months, I would have been okay with this. Joe is probably the worst booked monster in WWE, at this moment.
But WWE believes in the philosophy of 50-50 booking, which essentially means that they want their Superstars to trade wins until wins and losses become meaningless overall.
Which is why they had Rey Mysterio go over Samoa Joe in this big clash and probably set him up as a future title contender against Joe. I wonder if this is, in fact, the match that is planned for WrestleMania.
I would honestly be okay with a contest of this nature, between David and Goliath on the grandest stage. These two men could certainly tear it up.