"What he is doing with the club is the right thing to do," Routledge told BBC Sport Wales.
"It's not as easy as picking up a team and saying do this and do that and it works.
"You have managers like Pep Guardiola and Jose Mourinho who can go out and buy £50m, £60m or £70m players and maybe it's a bit easier.
"Here it's different. Sometimes you have to have a bit more patience and realise it's not a short-term process. It's going to be a long-term process but if that process gets you to where you need to be, it's worth sticking with."