Pourchaire finished as runner-up in the 2022 title fight to Felipe Drugovich, despite having been the pre-season favourite.
Despite suggesting he would not come back for a third year in the series, Pourchaire returns to F2 this season, with reigning FIA Formula 3 champion Victor Martins joining as his team-mate in place of Frederik Vesti.
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Philippe says the decision took a long time to come about, but it was ultimately decided that Pourchaire required “a bit more experience, a bit more maturity” before moving up to Formula 1 with Alfa Romeo, whose reserve driver he serves as this year.
The team boss also believes “we didn’t see yet the proper Theo”, given that he is still only 19, adding that he felt Pourchaire had progressed too quickly up the feeder series ladder.
Asked whether the experience would help Pourchaire’s title chances, Philippe said: “It took us a long time to make a decision on what was the best for him for 2023, and I think at the end of the day and what his F1 team decided, is that he needed probably a bit more experience, a bit more maturity, and also it’s better for him to repeat something than to stay one year without racing.
“On my side, I really think that we didn’t see yet the proper Theo, because he still is only 19, he has done three real years of motorsport, three or four years, and I think he still has a lot of things to learn.
“I think this is a good process for him to repeat this and do a third year.”
ART had a torrid second part of the season, with Pourchaire retiring from three of the final seven races, including the season finale in Abu Dhabi after a bird flew into his radiator.
Pourchaire was just 21 points behind Drugovich entering the summer break, but finished the season 101 points adrift of his Brazilian rival.
“There are a lot of things to say,” Philippe said.
“Last year, we didn’t deliver what we should have done, both on the team’s side and the driver’s side.
“I think it’s not one thing that went wrong, it’s many many little things. For sure, also Theo as we all know like many young drivers now, stepped up the categories very quickly and we should never forget last year he was only 18-years-old.
“It was really the first time he was repeating a category, in a way, in the approach that was completely new for him.
“I think we haven’t been lucky, as a team we haven’t been good every time, Theo did some mistakes, so all in all, I think some of it was there, but not every time, and we have never been capable to repeat three, four races in a row with good speed that could have brought us more confidence in the team.
“At the end of the day, you have to accept that Drugovich and MP did a fantastic job and they were there all year.
“At some point during the summer we thought we would be able to recover this, and after coming back from the summer break we did one mistake, two mistakes, and after, you know how it is.”