With a number of key players set to leave the club this summer, Ryan conceded that next season will not be easy.
"It will be a tough season next year and I think everyone needs to understand that," he said.
"I think once we start to recognise that and get the processes into place, people will understand how hard they have to fight to be in the Premiership and to be competitive in the Premiership."
Ryan started his role at Warriors after Saturday's match against London Welsh and was unveiled at Sixways on Tuesday. And the new boss now has less than four months to prepare the club for next season.
He continued: "We've just got to get our heads down and work. Yes, I'll try and make it better. But we've got to stop this illusion that coaches have got magic wands. They haven't.
"This will be a hard season with people having to work way beyond what they've had to work before. If we get that right culturally, then we can start to build."
Warriors have already announced the signing of eight new players who will join the club this summer. But Ryan believes it will take time for Warriors to turn their fortunes around.
He added: "I haven't taken this role because of the short-term. It's not based on where the squad is at the moment. I've taken this role because of the excitement about where I think it is in the long-term.
"I felt I could restructure a place which could be sustainable in the long-term. We have to recognise where we're starting from and how we improve it.
"But at the same time we've got a Premiership season that we've got to take on board and we're going to have to fight very hard to make sure we can compete."