Premier League referee chief Mike Riley conceded that there have been four clear-cut errors made by VAR since it was introduced at the beginning of this season.
"We are constantly learning," Riley told Sky Sports on Thursday after a meeting with Premier League shareholders where the matter was discussed. "On these occasions, the judgment should have been that it was a clear and obvious error."
The most notable error was Fabian Schar's equalizer for Newcastle against Watford. Riley admitted that VAR official Craig Pawson missed a clear handball on Newcastle's Isaac Hayden, which ultimately helped relegate the Hornets to a single point in a 1-1 draw. Watford currently sit bottom of the league and were the first club to dismiss their manager when they sacked Javi Gracia during the international break.
Riley also said Manchester City should have been awarded a penalty during their 3-1 victory at Bournemouth when David Silva's foot was caught by Jefferson Lerma.
Overall, it's been a mixed bag for the Cherries, with Riley adding that Leicester City midfielder Youri Tielemans should have been shown a red card for a stamp on Bournemouth striker Callum Wilson in the Foxes' 3-1 win at the King Power.
Finally, West Ham will feel aggrieved after a clear foul on forward Sebastien Haller by Norwich's Tom Trybull was apparently missed by the replay technology.
"Out of the four match rounds there's been some really good examples of where we've intervened," Riley said. "Six incidents where the VAR has advised the referee and we've got a better decision."
Riley added that acknowledging the growing pains of VAR during Thursday's meeting was a step in the right direction.
"What we've talked about this morning is the four instances where actually the VAR didn't intervene," he said, "and had we done I think it would have been a better understanding of the role the VAR plays in the game."