McLaren says a lack of communication and clarity of roles within the Formula 1 team were the key factors that triggered the problems that were exposed in 2018.
McLaren hoped that switching from Honda to Renault engines for 2018 would put it back in the fight near the front of the grid, but the team's car design was disappointing and it struggled for much of the campaign.
The team's competitive difficulties prompted an organisational overhaul that CEO Zak Brown says was needed to address historical issues that only came to light through its tough season.
When asked by Autosport about what had gone wrong at the team, Brown said: "It was the legacy issues that ultimately created this year's race car. "Lack of communication amongst the group, lack of clarity about roles, KPI [Key Performance Indicator] setting - all came from the past.
"Not one single person was at fault, but when you have CEOs and team principals in and out, and racing directors in and out, it is hard to get a path forward. "Specifically and technically, we now know what we have done wrong."
While a fundamental aerodynamic problem with the MCL33 meant major progress could not be made on track, Brown says suggestions that McLaren was left confused and stopped developments early on were inaccurate.
"A lot of the development that has been reported - like we stopped developing the car in Barcelona - was totally inaccurate," he explained.
"We had tonnes of bits going on the car up until the US Grand Prix.
"Some of those were to address the current car and some of those were to validate what we understood were the issues with this car, so we didn't replicate those issues going forward.
"What we have done is focus on getting that fixed - we have done everything from personnel changes to structural changes to get the right people in the right places with the right goals and the right KPIs.
"So when we go to develop the 2019 car we don't replicate those same issues and it is a road to recovery."
McLaren is still awaiting the arrival of new technical director James Key, who is set to join at some point next year once his current contract with Toro Rosso expires.
In the meantime, Brown believes the current design staff are on top of what needs to be done to make progress in 2019.
"It is a recovery progress because we don't have people like James yet in place, so it is journey, but I am confident we have identified our personnel and structural [issues] that ultimately led to the technical issues," he said.
"From a car standpoint, it is primarily being led by Pat Fry and Andrea Stella but it is a big group.
"Those two guys are very joined up and that is one of the issues we had. Of course, we had three [before] and they were not as joined up as they should have and could have been."
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