Nuno Espirito Santo has revealed his concern over Wolves' lack of consistency.
They have not won back-to-back games in the Premier League since beating Fulham and then Leeds at Elland Road in October.
Wolves host Leeds at Molineux on Friday after Sunday's 2-1 win at Southampton left them 12th in the top flight.
Victory would take Wolves above their opponents but Nuno remains worried about his side's inability to back up previous results.
The Wolves boss said: "It's very concerning, we are always trying to improving and reach our best performances. We want to be good and consistent and work hard to achieve that.
"We are lacking a lot of the things we are trying to search for in the games.
"We go match-by-match, we have a new challenge and a very difficult challenge, this will always be our philosophy.
"We always face a situation where we assume we have to improve and cannot say when we are going to reach the best. There is never the best, there are always new things.
"Our approach is improving match after match. We have to improve some aspects of our defensive organisation, there are still a lot of mistakes which we want to avoid.
"Leeds are a very good team, very special and unique in the way they approach the games. They have a fantastic squad, a very good manager (Marcelo Bielsa) and we realise they are very competitive. It will require the best of us."
Willy Boly (hamstring) and Daniel Podence (groin) remain out with Raul Jimenez (fractured skull).
"He (Jimenez) is training, he has been able to integrate into some of the training sessions and he is improving and doing well," said Nuno.
"We have to be very careful and follow the protocols but keep positive because he is doing well.
"We are delighted, but know it'll take time. He is going in the right direction.
"He will keep improving his fitness, follow the protocols and do consultations with the neurosurgeon. It requires patience but it's moving in the right direction."
