Everton are on a run of just two defeats in their last 12 matches, having lost their opening four league games of the season.
City, winners of an unprecedented four successive Premier League titles, by contrast have lost nine of their last 12 games as they prepare to welcome Everton for Thursday's Boxing Day clash at the Etihad.
"They (City) have enjoyed so much success under Pep (Guardiola) over the years that everybody seems to be under this impression that it's when, not if, it turns back," said Dyche.
"I don't know all of Pep's history, but I think it's unlikely he's had too many spells like this.
"You'd think at some point it happens, even to the best, and he is arguably one of the best ever, but for him to have a testing period actually shows how tough the game is even for the top sides."
The 53-year-old Englishman added: "The details, even for the top teams, if you don't get them right, then things don't work out for you. They'll be trying to correct that.
"We're in the process of correcting somewhat what we were doing. We still need to win more games, obviously, and score more goals.
"It's not like you go there and think, 'We're going to win just because'. We've got to go and deliver a performance. We've got to play hard, we've got to play strong.
"They haven't all become terrible players overnight. He (Guardiola) certainly is not a terrible manager."
Dyche will be without the consistent Ashley Young, suspended after a fifth yellow card, on Thursday.
But his absence means club captain Seamus Coleman is set to make his first start since the end of August following an injury-plagued campaign for the 36-year-old Irishman.
"He's been very unlucky this season," said Dyche. "When he came back for pre-season, super fit, we spoke about his other options and he said, 'No, no, I'm clear-minded. I'm going to continue playing'.
"He signed another contract and he held his end of the bargain without a shadow of a doubt."
© 2024 AFP