Why do people call Triple H Triple H?

Answer 1

because that is the name of his theme song

"A lot of folks call themselves students of the game. I AM the Game. There's no one who eats, breathes, and lives this business more than me!"

-Triple H

In other words, HHH is claiming he's worked harder and learned more than any wrestler before him, so he pretty much IS the Wrestling business rather than just a part of it. Hence, "The Game".

Answer 2

before he became triple h, his name was "hunter hearst helmsley." since the initials are h.h.h , well, you get the idea.

Answer 3

triple h's nick name is triple h because his old name was hunter hearst helmsley and that was three h's and he became triple h