Pep Guardiola claims his quadruple-chasing Manchester City side are still some way off reaching their potential.
City are looking unstoppable having won their last 19 matches in all competitions.
They are 10 points clear at the top of the Premier League, on course for the Champions League quarter-finals, through to the Carabao Cup final and involved in the last eight of the FA Cup.
Guardiola has already won six major trophies with City, including back-to-back titles in 2018 and 2019, but he is convinced the best is still to come.
"If I did not feel we could get better, I would not have extended my contract here – 100 per cent," said the Spaniard, who last year committed himself to the club until 2023.
"If I extend my contract, it's because they convinced me still that we can do better. If not, the team would be over.
"I came here to win in England and we have done it already, I came to play in a special way and I did it. The job is done, but still I have the feeling we can do better.
"Still I feel we can win more and make our fans proud."
Overall, Guardiola has won 29 trophies in his glittering managerial career, which includes glorious spells in charge of Barcelona and Bayern Munich.
With an emphasis on an intense but attractive style of play, the fiercely-driven 50-year-old has been one of the most influential coaches of his generation.
He remains reluctant to take credit for his team's successes, however, modestly preferring to praise the players.
Earlier this week he claimed his success at City was down to the club's enormous spending power. It was thought this was a sarcastic dig at critics who have often overlooked his abilities to focus on the talents he has had at his disposal.
He insists this was not so and maintains that the players, and the winning mentality already embedded in the club, are the crucial factors.
Guardiola said: "I would be grateful to say the reason behind this success is because I'm so handsome but it's not like that. It's the players.
"The big clubs have incredible success, in South America and Europe, and it's due to the quality of the players, the mentality.
"The manager can seduce them to have this mentality a little bit but the organisation too. Our chairman does not want one day of sleep, doesn't want to rest. He pushes me. We push each other to be better and better.
"For a short time you can do it without top players – half a season, one season – but sustaining for a long time, (you need) top-quality players.
"I never in my 12 years as a manager scored a goal, never. I never saved a penalty. The artists are the players. All we can do is help them."
In his determination to deliver that help, however, Guardiola admits he finds it difficult to rest.
"Sometimes I shout at my players and I should not do it but I cannot control it," said Guardiola, whose side host West Ham on Saturday.
"It's the way I am. I don't want to be fake to myself. I love my job, I enjoy being a manager and I want to be better.
"I want to try to reach the team every day to do it better. I demand a lot of myself and I don't want to feel weak. I have to be there – they have to know that I am not resting."