Command and Conquer Generals and synchronisation

I had a three player game of C&C Generals last night at a friends house. Close to the end a big box appeared saying the computers were out of sync and it closed. Generals isn’t the only game to do this, many do (Star Trek Armada was a bad one for it) and there really is no reason. If the game goes out of sync and the clients can tell they’re out of sync why not just pause and it request the current game state from the host? It can’t be that different to everyone else and it’s better than quitting.