Zak Brown says new McLaren principal Andreas Seidl took "the politics" out of the team in 2019.
Brown, still McLaren CEO, says that when he arrived at McLaren in the wake of the Ron Dennis era, "There were many chefs in the kitchen".
"Many things were happening in the company and among the shareholders," he is quoted by Spain's AS newspaper.
"There was a lack of clarity in leadership, but now it all has been put on one person and Andreas has done an excellent job."
Indeed, from the misery of the Honda era, McLaren has just beaten Renault to fourth in the constructors' world championship.
Brown said of former Porsche chief Seidl: "Obviously he didn't build the car, because that was done last year.
"But he has brought clarity and leadership to the organisation with a simpler structure involving James Key and Andrea Stella and a clear mandate for what each person should do," he added.
"He took the politics out of the team, because when a leadership position is missing things can become political.
"With that, better developments have come to the race car and many other things started to come together which is essential for any business. We needed to reverse our bad streak from the past," Brown said.
However, Brown acknowledged that McLaren's next step - catching up to the top three teams - will be even more difficult.
"One of the things we have done recently is to recalibrate our expectations," said the American.
"We thought that as soon as we changed our power unit we would be back at the front, and clearly we weren't. But the first thing we had to do was make sure that we are not going backwards.
"We also know that the budget cap will have an impact and will play a role in this process. There is still time for us to get where we want to be," he added.