A John Terry own goal earned the Eagles a lifeline in their battle against relegation.
Mourinho absolved his defenders - Branislav Ivanovic, Gary Cahill, Terry and Cesar Azpilicueta - of blame for the loss to Palace, but was not shy at pointing fingers at others.
Mourinho said: "My four defenders, phenomenal performance, as always. The others I'd prefer not to analyse individually."
Asked what quality is required for his side, Mourinho said: "I cannot say in front of the cameras. I can write it on paper."
Offered a notepad after the media conference, the Portuguese wrote "balls".
He had made his discontent clear.
"We missed some qualities," he said. "Mentality and a little bit of quality. Mentality because the opponents beat us clearly on that. Strong mentality, aggressive, committed.
"Every one of them played, I think, at the top of their potential and that, in football, is important.
"Clearly we have some players, because of their profile, who find it difficult to perform in some profile of matches.
"You have Ivanovic, Terry, Cahill and Azpilicueta and they perform in the sun, in the rain, small pitches, big pitches, aggressive teams, non-aggressive teams, possession teams, not possession teams and they perform every game from day one to the last day.
"And you have other players who are fantastic in some matches and disappear in other matches."