Antonio Conte was frustrated that VAR did not reverse a penalty decision against Napoli as they played out a 1-1 draw with Inter on Sunday.
Hakan Calhanoglu failed to convert the spot kick in question late in the game, with the Turkish international having equalised for the hosts after Scott McTominay's opener.
Despite the decision not affecting the result in the end, Conte criticised VAR for not overruling the referee's decision to penalise Andre-Frank Zambo Anguissa for a foul on Denzel Dumfries.
"Can they [VAR] only intervene when it suits them? A decision from the referee like this can transform a match and VAR cannot do anything about it," Conte told DAZN.
"Either VAR is there to correct errors or it is not. If there is an error, it has to intervene. It really angers me, but it does to all coaches. It has to intervene if there is a mistake.
"If there is VAR, it must be used to correct errors or show the referee situations that he did not see. If it's a clear error, and it was, then why should [referee Maurizio] Mariani be allowed to just do that."
Despite his frustration with refereeing decisions, Conte was satisfied with his team's performance, as they held strong against a spirited second-half display from the Italian champions.
"I said that we would not come here to just be sparring partners against the strongest squad in Serie A, so it was important for us to face them with strength, character, accepting duels all over the field," he said.
"On that score, I am very satisfied. It was not easy to play here. We all know that we are making improvements and working hard, otherwise, you don't come to San Siro twice and also against Juventus without defeat.
"The lads are proving themselves, though, of course, we could've done much, much more in terms of quality today. There were too many errors, a lot of technical errors, but I am sure there will be further improvements."
Napoli's point ensured they stayed top of Serie A heading into the international break, moving them to 26 points in what is shaping up to be a tight title race. Conte's side sit one point clear of Atalanta, Fiorentina, Inter and Lazio.