In Guardiola's first season in charge, the blue half of Manchester finished third in the Premier League table without silverware.
City have started the 2017-18 campaign well by winning five of their six games in all competitions so far, but De Bruyne has played down expectations.
"There's a project going on if everyone looks at the big picture," the Belgian told the club's official website. "A lot of older players were released and we bought almost only players that are 23 or under. So it's a new team, a new project, obviously it takes time and it takes money."
The North-West outfit will turn their attention to the EFL Cup this evening when they face West Bromwich Albion at The Hawthorns in the third round.