Dan Fallows' removal as technical director at Aston Martin came as the team hadn't matched its expectations for 2024, according to performance director Tom McCullough.
McCullough noted the ex-Red Bull aerodynamicist's contributions after joining Aston Martin in 2022, which carried into 2023 as the team made a concerted leap from F1's midfield to podium contention.
However, results tailed off toward the latter half of last season, and Aston Martin made limited progress over the winter as it has largely assumed a lonely vigil in fifth place in the constructors' championship.
After a series of high-profile technical hires, including the signing of Adrian Newey (his arrival expected in March 2025) and the addition of ex-Ferrari chassis lead Enrico Cardile, it was also decided that Fallows would be moved elsewhere within Aston Martin's hierarchy.
"The performance of the team this year hasn't been at the level that we've all been wanting it to be at," McCullough said. "So we haven't quite delivered there and that's basically been a decision made by the team.
"I sat next to Dan for the last two or three years since he's been here, working closely with him, he had a really big impact on the development of the '22 car, the '23 car, he's brought a lot to the team, to be honest.
"From that side, it's been good fun working with him. But ultimately during '24, we haven't delivered on track to the level that we know we're expecting to and wanting to do.
"The development of these cars has been hard and ultimately it's a performance-based industry, isn't it? And the team's made the decision to make some changes."
McCullough later explained that he felt the team had been able to get its head around the difficulties presented by the AMR24, and was confident it would be in a much better place for 2025.
He added that both Fernando Alonso and Lance Stroll had been consistent in their feedback of the current car, and understood their struggles to cope with a drop in performance this year.
"I really do think [we've got a handle on the car], but the proof of that pudding's in the eating, isn't it," McCullough said. "So, living in a CFD and Wind Tunnel world is one thing; I think that side of things is progressing reasonably well.
"It's a relative game. So until that car hits the track and you see what it does in reality you don't know for sure.
"But I do think the learning we've been through this year is putting us in a good place, but obviously we're wanting to have that a bit earlier in all reality.
"I think the two drivers are pretty aligned in their feedback and the limitations of the car. I think they're both wanting a more performant car, they want to be fighting for points week in, week out, and at the top end for points.
"And when we don't give them a car that can do that, they're never happy, and we understand it's difficult.
"We have a lot of meetings with the drivers, either online or at the factory, explaining to them what we're doing, why we're doing, what we've found. Just keeping them in the loop so they understand, I think is important."
