I was the ref for a u13b competitive game. In the second half, I cautioned a player for a late sliding tackle which tripped the opponent, after the ball was gone (USB for reckless tackle). As I'm recording the details, I think to myself, "Hmm, this player has just about hit the limit for persistent infringement. Now what to do?" I decided to say nothing at that point. Maybe having gotten a caution he would calm down. But if he committed even the slightest infraction after that, I was going to have a good chat with him, indicating that he was almost gone. One more foul was going to do it. As it turned out, this player did not commit any more fouls. That might not have been solely because of the caution. His team was down by 2, and we had reached the time in the game where the intensity of play and emotions changed from despiration to resignation. Also, his coach pulled him from the game for a significant amount of the remaining time - whether in response to the caution or simply because his rotation was up, I don't know. But what if I had spoken to him earlier, warning him that he was fouling too much and that a caution was possible? Then he comes in with this reckless challenge - two yellows at once, = red?