Why do people hate LeBron? Because he does stuff like THIS (notice it's while the damn game is going on).
He's a mental midget, he's about as mentally weak of a superstar as I've ever seen in any sport. He gets frustrated so easily, when the going gets tough he starts screaming at teammates, stops playing as hard and just goes in the tank. He did it against Boston during his last season in Cleveland, against Dallas last year in the Finals. He did it in Game 4 against the Knicks this year.
And of course he has the ultimate attention-whore, "look at me!" attitude. Most stars have it to a certain degree but LeBron seems like he's more concerned with impressing people than winning games. Anyone who watched Bird, Magic, MJ, Kobe etc can tell pretty easily that this guy is basically a phony. But as someone else said, he's been a pampered baby his entire life so it's no surprise that he's the person he is. He's never had to overcome any adversity or really work that hard.
He pulls The Decision, fakes his apology for it and then has a gigantic championship-level celebration with Wade and Bosh before they ever even play a game together, talking about how they're going to win six titles. He's just a .