United spent over £170M this summer on a midfield revamp as Michael Carrick secured deals to sign Andrey Santos, Youri Tielemans and Carlos Baleba in a plan to bring Premier League experience into his engine room.
However, several of United's rivals spent over £100M on one midfielder, as Chelsea broke that mark to sign Morgan Rogers, and Manchester City twice went above it to land Elliot Anderson and Enzo Fernandez.
United are back in the UEFA Champions League this season under Carrick, but Cole believes top players are still unsure over a move to Old Trafford, based on the risk involved.
"You've got a finite life span as a player. If you're signing a five-year contract and it's a choice between United, City or Chelsea - you're going to go to City or maybe Arsenal," Cole told TNT Sports.
"That's because you know there's trophies to be won there. Look at the games this week as United lost to Brighton and Chelsea to Brentford.
"Brighton and Brentford were better in every aspect of the game. A title challenge for Man United this season is out of the question, they're in that next group down, trying to get third, fourth or fifth place."