The concept of a "dumb" rule in sports is subjective and can vary depending on personal opinions and perspectives. What may seem like a dumb rule to one person could be an essential aspect of the game for another. However, there are a few rules in different sports that have been criticized or debated due to their perceived lack of logic or fairness. Here are a few examples:

1. The Infield Fly Rule in Baseball: The Infield Fly Rule is a rule in baseball that aims to prevent an unfair advantage for the defensive team when there are runners on first and second base (or bases loaded) with less than two outs. If an infield fly is hit, the batter is automatically out, regardless of whether the fielder catches the ball or not. Critics argue that this rule can be confusing and unfair, as it takes away the opportunity for a double play or a potential error by the fielders. However, proponents argue that the rule is necessary to prevent the defensive team from intentionally dropping a pop-up to initiate a double play.

2. The Offside Rule in Soccer: The offside rule in soccer is designed to ensure fair play and prevent goal-hanging. A player is considered offside if they are nearer to the opponent's goal line than both the ball and the second-to-last defender when the ball is played to them. However, the offside rule has been a subject of controversy and debate due to its complexity and the difficulty for referees to make accurate decisions in real-time. Critics argue that the rule slows down the game, leads to inconsistent calls, and often penalizes attacking players who are only marginally offside.

3. The Tuck Rule in American Football: The Tuck Rule, which was abolished in 2013, was a rule in American football that defined a fumble in specific situations. According to the rule, if a quarterback lost possession of the ball while attempting to tuck it back into his body after a passing motion, it was ruled an incomplete pass rather than a fumble. This rule gained infamy during a playoff game between the New England Patriots and the Oakland Raiders in 2002. The rule was heavily criticized as it seemed to favor quarterbacks and led to controversial calls where a clear fumble was overturned.

It's important to note that while these rules may be considered "dumb" by some, they were implemented for specific reasons to maintain fairness, prevent intentional rule manipulation, or ensure player safety. Rules in sports are often a result of years of refinement and trial-and-error, and what may seem illogical or unnecessary at first glance may serve a purpose within the broader context of the game.