Cheika blooded five players in the England series, including Western Force lock Adam Coleman, who played the entire second half after Rob Simmons was forced off with a high grade AC joint injury.
"I genuinely don't want that as an excuse for not winning because we've had opportunities to win the games with the new players," Cheika said.
"Samu Kerevi and Dane Haylett-Petty have both shown themselves to be up to it. Rory Arnold has come in and played good footy and even Coleman tonight.
"A couple of players that we've liked in the background that haven't played games that we think will play in the Rugby Championship as well, we add those to the guys we get back from injury and Europe, and our squad will grow."
Cheika wasn't happy with the standard of refereeing in the England series.
"It's cost us lots of points hasn't it, you can't deny it," Cheika said.
He was bemused by Welshman Nigel Owens' ruling to play on after a kick from England inside centre and man-of-the-match Owen Farrell hit the wire of the overhead Spidercam.
The ball landed in the hands of another visiting player and England went on to score a crucial try minutes later.
"You can't hit the camera wire and play on," Cheika said. "He said over the microphone '50-50' for each team."
"If you're waiting to catch a ball and it hits a wire and all of a sudden you're out of position and the ball has been kicked to us, I don't see how that can be play on."
Cheika said his captain, Stephen Moore, missed a lineout throw when he was pushed in the back by a linesman, though the hooker said he didn't believe that was an excuse for his error.
Cheika said there were other factors for their losses.
"The major part will be to assess what we need to do to eliminate the small errors, the (lack of) accuracy that is shutting down the play we are creating," he said.
"I want us to be able to play that type of footy and we can do it and we've done it before without as many errors.
"That means working harder, being fitter, being more accurate, getting guys to fulfil their potential more."
-AAP