The Dons lost their unbeaten record this season as they crashed to a 2-0 defeat at Exeter on Saturday.
"I have to give Exeter credit because they were lively, but the difference between the two teams was phenomenal," said Ardley.
"We had a lot of chances in the second half, but that does not mask our performance.
"It is about how we respond to this now. I have told them that you cannot turn up anywhere in this league and not do the other side of the game.
"During the first half we were off the pace. As a manager I know that is not good enough and the players know that."