Courtois took part in two Nations League games for Belgium against France and Italy in the Semi-final and third-place play-off respectively.
Advocating for enough rest for players, Courtois has slammed UEFA for focusing on money than the players' welfare, stressing UEFA treat players like "robots".
"This game is just a money game, we have to be honest about it," he told Sky Sports.
"We just play it because for Uefa it is extra money and it is an extra game on TV.
"OK, for us it's a good game because it's against Italy and for Italy it's a good game because it's against Belgium, but look how much both teams changed their players - if we had both been in the final there would have been others playing.
"This just shows that we play too many games," Courtois continued. "Next year we have a World Cup in November, we maybe have to play until the latter stages of June again. We will get injured and nobody cares about the players any more.
"After a long season we will have to play four games in the Nations League again, we will have two weeks' holiday and that's not enough for players to be able to continue playing 12 months at the highest level.
"If we never say anything it will always be the same. They (Uefa) can be angry about other teams making a Super League but they don't care about the player."
