As a coach, there is a tendency to want to review the game with the team as soon as the game is over (and this desire seems to up dramatically when the team has played poorly).  However, it's important for the coach to realize that this is the absolute last thing most players want to do at that time.

When the game is first over, the players should get something to drink (whether it's water or some type of sports drink) in order to begin re hydrating, and then start right in with a cool down session (similar to the warm up dynamic but typically in reverse order so that it slows down and instead of increasing the pace) and take a fair amount of time doing this.   Next have the players take one more drink, have a very short discussion (time and date of next practice, next game etc) and then let the players leave.

The main argument for discussing the game immediately after the game is that it's fresh on the players minds and because of this, they will remember all of the details.  While this is true, the problem with this is that while they might remember the details, they will have so many other things going through their heads, that they don't concentrate enough to take advantage of these details. So often, when I see coaches talking to their players immediately following a game, the coach is talking and the players are looking down at the ground, or looking in other directions.

When coaching youth players, it's important to realize that there are usually family members waiting for the players.  Or, their friends are waiting for them.

Even if this is a tournament where there are two games a day, the coach might think after the first game the players have no where to go so that is a great time to talk to them about the game.  However, it's been my experience that it's much more effective to wait and have this discussion prior to the second game rather then after the first game.  This allows the players time to get away, “decompress” and be ready to focus on things they can do to improve.