"We felt that match fitness was the key for Juan," Jackett told the club website. "To get him up to Championship standard he would need to play games and it is hard to go from nothing straight into the Championship.
"That can be tough, and while the odd player does it most people don't – you need a run of games and need to build up.
"So it was nothing to do with his ability levels, just that he hasn't played."
Agudelo, who represents USA at international level, did sign for Stoke last summer, but the Potters failed to secure a work permit for his services.