How are pro wrestling superstars actually picked or made?

Seeing that pro wrestling is all fake and scripted who decides who gets to be the superstars like past superstars Goldberg, the Hulk, The Rock, etc? Do focus groups pick them, the fans somehow pick them or do the people at the top anoint who they feel will bring in the most bucks? It can’t be because they earned it like boxers and ultimate fighters who got to the top actually combating someone unscripted and winning the match.