It was not his TALENT. He DID have excpetional talent, but it was not skill that got him 894 goals, 2857 points in 1487 games. There were quite a few players more skilled than he was in my opinion.
2) Was not GOOD LINEMATES. In Edmonton especially, Wayne had tremendous support, in a powerhouse team that played a run and gun style of game. He had great players and leadership of players like Mark Messier to guide him to the cup
3) Was not SIZE/STRENGTH. He was a small player and consistently registered last on his teams strength tests. He had speed of a bullet and had the greatest hands of all time

The early training, good linemates, and exceptional talent got Gretzky very far. But the one thing that set him apart was his unmatched hockey mastermind. He was way far above anyone, even Lemieux and Bobby Orr. Gretzky had the ability to get into the minds of the defensemen and goalies. He knew what they were thinking. He knew what they expected him to do, and then did the opposite. He could read what plays they would try to make. He also knew where the puck was headed. His quote that “He goes where the puck is going to go, not where it is” was one of the keys for his success. He was able to read a play, then make a decision on the best possible play. His ability to read the play better than anyone else and to read the minds of opponents was what made Gretzky great. Even if players knew what he was going to do, he would speed past them deke them out and make the goalie look silly