Former Manchester United manager David Moyes believes the club have fallen out of competition for silverware because of their ambiguous transfer strategy.The Red Devils have won just three trophies - the Europa League, FA Cup and League Cup - since Sir Alex Ferguson's retirement in 2013.Despite their big spending, United have finished outside the Premier League's top two in five of the last six years.And Moyes believes that the club's uncertain approach in the transfer market has hindered their progress, as they have purchased players based on their marketing potential instead of playing ability.“For a while it would be difficult to know what direction United have gone in," Moyes, who spent 10 months in charge at Old Trafford after Ferguson stepped down before being Louis van Gaal took charge, told The Mirror."Whether they have been signing players for marketing, which they are fantastic at, or whether it has been signing players for on the pitch, I am not quite sure.“What Manchester United had was great values and class. Manchester United’s values weren’t always to buy the most expensive players but to do it their way which was bringing in the boys from the academy and picking up the best young players.“Now and again there would be a sprinkling of stardust, like an Eric Cantona, or someone who they signed to make the difference, like Robin van Persie.“I never thought they were a club who thought it was all about spending the money, but if they needed to, they could.”United have spent £50 million ($63m) to land Aaron Wan-Bissaka from Crystal Palace and a further £15m ($19m) to sign Daniel James from Swansea, both 21, while they are reportedly close to signing Bruno Fernandes from Sporting for £62m ($77m).Meanwhile, Paul Pogba continues to be linked with a move away this summer, with Real Madrid the favourites to sign him.United begin the 2019-20 Premier Leauge campaign with a home match against Chelsea on August 11.