Former Formula One champion Michael Schumacher insists that a lack of funds was "a factor" in Mercedes' failure to win during the German's three-year stint with the team.
The manufacturer makes no secret of the fact that it does not spend as much on its F1 team as the likes of Ferrari and Red Bull and has denied that it plans to increase its expenditure in the near future.
"It's a factor," Schumacher commented to Auto Motor und Sport.
"Over the years, Red Bull built an infrastructure and has a budget giving them the possibility to respond to anything in the best possible way.
"It is nothing more or less than what we had at Ferrari," the 44-year-old, who won five titles for the Maranello-based team last decade. added.
Since Ross Brawn bought out the team in 2010, Mercedes has never finished higher than fourth in the Constructors' Championship, but with the acquisition of Lewis Hamilton as Schumacher's replacement signaled their intent to challenge for top honours in the sport.
"I know that deep in his heart he wants to win all the time," team boss Ross Brawn is quoted by Germany's Die Welt, "but he must also understand the course of development we are on at the moment."
Mercedes non-executive chairman and a former World Champion Niki Lauda agreed.
"I prefer a sober analysis of the situation rather than promising something we cannot deliver," the three-time winner commented.
Nevertheless, Hamilton's new team-mate Nico Rosberg insists that the team is making progress, despite appearing to stall during the second part of the season.
"If you walked through the factory today, you would see a massive improvement compared to three years ago," the German noted.