People get WAYYYY too caught up in having to finish fights.
Floyd Mayweather, arguably the greatest boxer alive today, is nothing more than a counter puncher. He is not a Shane Mosley or Manny Pacquiao in style, but yet no one has proved capable of touching him.
I actually heard one great comparison, in the sporting world at least, to GSP. That was Tim Duncan. You watch Tim play, and he isn't some other world athlete like a Lebron or Kobe. He kills you with fundamentals. How to get proper spacing, drop-steps, bank shots, positioning. You watch him play and you see him dominate doing nothing flashy, but everything right.
With GSP, you won't see the Wanderlei, Anderson, Fedor, Junior, or whomever. The guy does what he has to do to win.
Compare it to the Cowboys. People get ticked off when we constantly looked for a big play, as Garrett was prone to running a ton of vertical routes. Big plays please the fans. Except when the big plays lose, then people become critical.
You win, however you have to do it. Fans are going to find a way to criticize regardless. It's the nature of the sport, even as weird as it can be sometimes.