Williams chief executive Jost Capito justified the decision to part ways with ex-team principal Simon Roberts, saying that the former's "capabilities" didn't fit within the outfit's new organizational structure.
Roberts took over last year from former deputy-team principal Claire Williams in the wake of Williams' takeover by US investment firm Dorilton Capital.
But earlier this month, Capito announced Robert's departure as part of an internal restructure that "further streamlines operations as part of the long-term objectives to return Williams to the front of the grid".
The British outfit's organization now relies more heavily on its new technical director, François-Xavier Demaison, who will supervise all engineering work at Grove and on site on race weekends.
"During the first 100 days, I took a huge effort to understand how the teams work," Capito said.
"I talked to more than 80 managers in one-to-one meetings, and I asked them all the same questions. So I got a good overview what we should change, what we should keep.
©Williams
"It became clear that engineering should be all in one hand: track engineering, design, aero, should all be in one hand.
"That should be under the technical director, and that should be a technical director who has done all jobs in racing, who has been at a drawing board, who has been a race engineer, who has done R+D, and FX is exactly that person.
"You have the technical director in charge of everything that is related to the car, and you have a sporting director who is relating to everything not with the car in the race team, and makes the race team work and function," added the former VW Motorsport boss.
"So the technical people don’t have to bother, they can fully focus on the car and on the performance.
"With that, the capabilities that Simon offers didn’t fit in that system. Simon did a fantastic job through the change of ownership, to keep the team together.
"I think that’s always a very critical situation for a team, and the team can’t fall apart and get in a dip. He did a fantastic job keeping the team together, and we’re very thankful for that."
Williams has yet to nominate its new sporting director, but Capito said the team has received some "very good applications", including from individuals with no prior F1 experience.
"I think that it’s not necessarily needed," Capito said. "Sometimes it’s good to have a view from outside.
"I think I saw [McLaren team principal] Andreas Seidl’s interview from last week, where he said the reason he can do this job is because he’s been outside of Formula 1!"
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