Why Do Footballers Need Warned?

You often see during a game, the referee talk to a player, remind him that he needs to win the ball, not take the player etc and that if the player does that again they will be booked but why? Surely a warning is for people who don't know the rules already, not for those who do know them.

Football, like any sport has rules; this is a good thing. It sets the restraints players, managers etc have to work within. Anyone who plays football starts somewhere, watching their mates at the park as a kid before joining in themselves or watching it on TV and wanting to be their heroes etc. They pick up the fact that play stops when a bad tackle comes in and a free kick is awarded. They pick up the fact that outfield players are booked if they handle the ball and / or a penalty is given if they do that in their penalty box. In short, they pick up the rules as they go.

By the time they get to the professional stage they know the rules inside out. They know what they can and can't do. They also know a lot of other rules placed on them dealing with drugs tests, interviews by the media etc too. Why do they need warnings on the pitch? Why should they get warnings on the pitch?

There is the angle that in the heat of battle the players are so eager to win that sometimes their judgement gets the better of them but I don't buy that. Attacking players don't get so eager to score that they floor the goalkeeper with a right hook as a corner is coming in to prevent him from catching it. They know they can't do that, and if they do they face a red card, a ban and a disciplinary hearing. They know they have to play within the rules, even in the heat of battle.

Of course you couldn't just take away the warnings without any warning (pun not intended). You'd have to start on the same day for every team. You'd have to also inform every team that there are no more warnings, and if their players break the rules the penalty for those rule breaks will be enforced. If that means the first tackle a player makes is a yellow card tackle then he'll get a yellow card for it. It's up to the clubs themselves to ensure that their players know the deal when they go onto the pitch.

The idea of warnings does seem to be treating players as goldfish who don't know the rules as they walk out to start a game, and have forgotten any warnings they got in their previous games as well as anything their coaches told them. If this was the case you'd expect one of the outfielders to catch the ball when it's passed to him. This type of thing happens all the time at the top level.....right?