4. League of Nations
The League of Nations was a great concept that was executed poorly. You had four men, who had a common denominator in terms of being non-American, in need of a story. All men were impact players and the stable had potential to be a super threatening stable. On paper, they were a credible threat with Sheamus being the WWE World Heavyweight Champion and Alberto Del Rio being the United States Champion.
That eventually fell apart when both men lost the titles and the group was dismantled by Roman Reigns. The group was endorsed by the Authority eventually and it played a part in dethroning Reigns as a Champion at the Royal Rumble later on. The League of Nations then took part in a feud with The New Day leading into WrestleMania. Despite the success, the stable fell apart shortly later when they exiled Barrett from the group.