4) 1999 Royal Rumble winner Mr. McMahon
The 1999 Royal Rumble focused closely on the legendary feud between Stone Cold Steve Austin and Vince McMahon. This was the rivalry that defined the Attitude Era. This period is often fantasized with fans forgetting some of the not so wonderful moments from this time. One of those moments came at the end of the 1999 Royal Rumble Match.
To finally get his hands on McMahon, Austin convinced him to enter himself into the 1999 Royal Rumble Match. Commissioner Shawn Michaels made Vince the #2 entrant after McMahon made Stone Cold #1. This Rumble centered on the shenanigans with these two before it came down to just them. The Rock cost Stone Cold Steve Austin the Rumble and allowed Mr. McMahon to win.
Some fans believe this was a necessary win for McMahon, who helped progress his story and establish the Austin vs. Rock feud. However, there were ways to do that without undermining the Royal Rumble Match. Mr. McMahon didn't even get the title shot at WrestleMania 15 with Stone Cold beating him at St. Valentine's Massacre to win the shot. Austin should have just won from the beginning.
3) 2015 Royal Rumble winner Roman Reigns
Roman Reigns is one of the most maligned Royal Rumble winners in history. Heading into the 2015 edition, Daniel Bryan returned and wanted to get back to WrestleMania. WWE were building up Reigns and looked to be setting him up for the big win, but Bryan's return made the fans desire to see him victorious again.
This all made the 2015 Royal Rumble Match that much more annoying. Not only did Daniel Bryan not win, but he came out at #10 and was eliminated after 10 minutes. Roman Reigns overcame the odds thanks to the Rock to win. When the Philadelphia crowd booed a returning Rock, WWE should have known they got it wrong. This was obviously Bryan's year... for a second time.