#4: Triple H (Five losses)

Much like another Superstar on this list (we'll get to them later), Triple H has always been criticized for not putting others over, but that certainly doesn't seem to be the case when the Game has appeared at SummerSlam.
The Cerebral Assasin was defeated by Brock Lesnar in 2012 in what was one of his biggest matches at SummerSlam, and he has also been beaten by the likes of Shawn Michaels, in their incredible street fight in 2002, a cage match loss to Mankind in 1997, a triple threat against The Rock and Kurt Angle in 2000, and another triple threat loss in 1999.
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Though he has had some major victories at the show as well (E.G. his Elimination Chamber win in 2003), it seems to be Game Over whenever the King of Kings appears at the August pay per view.