The Chelsea midfielder made the decision to leave west London on loan in the summer of 2017, joining Palace for the season.
"From 18 'til now has probably been the hardest time of my life mentally," Loftus-Cheek told the club website. "Midway through the [2014-15] season I went to the first team and I was training with the first team, I made my debut. That moment I was happy, [but] it felt like I just couldn't make that next step.
"It got to a point where in those years I hadn't played that much football. I was improving technically, but I felt like I needed the game time. I had to say something, to say I wanted to go on loan and play some football.
"To be at a team that was winning every week to a team that was fighting in games where you wouldn't have much possession, I actually really enjoyed being an underdog."