Skill matters more when the game has a limit as it's impossible to knock out an opponent by going all-in with a nutty hand. That kind of move isn't possible in a Pot Limit game. In a No Limit game, a player can overbet with a strong hand or even go all-in. In a Pot Limit game, it's more difficult to make deceptive moves. Betting is more predictable when the range of possible bet sizes is limited. This limits the amount of chips that can be won - or lost - in a single round. That means that a player can only raise by the value of the pot at the time. Omaha is mostly played as a Pot Limit game. This matters a lot when it comes to determining the nature of the game. Texas Hold'em is mostly played as a no limit game, which means any player can go all-in at any given time.
