"It definitely takes you time to settle and to adjust if you get into the first team at a very early age," Cattermole said in the Sunderland Echo.
"You're a kid. You don't have a clue what's at stake or what you have to do to get your performances right.
"As you get older you change your ways and realise how much this game means to people and yourself as well.
"I've changed drastically from the lad I was at 21, let alone 17 to 18."
Cattermole continued: "He came to Sunderland as a young lad and he's never really been given a chance.
"When he has been, if you don't take your chance in the first couple of games, you don't get much longer - results are that important.
"But he's shown people what he's all about now after getting experience from his loan spells and hopefully he will get better and better."
For the big stories and the banter follow us on Twitter: @tribalfootball