Jean-Philippe Mateta struck for Palace, but Beto and Charly Alcaraz scored the goals for Everton in their 2-1 win.
Glasner later said, "We all feel disappointed and frustrated as it was a game I don't think we should lose. We have too many decisive mistakes. We had some chances and when you make mistakes they took the chances that we gave them.
"We said before the game it will be a very close game and both teams neutralise each other in different parts of the game, We had two or three big aces in the first half before they scored and it was a big gift, the first goal.
"Football is a game of momentum and you need to take the momentum. We didn't get so much pressure and we were a little bit worried about the long balls. One of their set plays decided the game.
"It is a team win or a team defeat and today it was a team defeat. We have to find better solutions. Then we can learn from it and win those games."