He won his first trophy as City boss in the Carabao Cup, and they are four wins away from the Premier League title.
City have one foot in the Champions League quarter-finals, holding a 4-0 advantage before Wednesday's last-16 second leg at home to Basel.
"To think about joining these kinds of teams [like Barcelona], you have to be there a long time," Guardiola said.
"We won one title but it is not good for us comparing with that team. They dominated the last decade - 15-20 years with different managers, different players. Every season they won a lot of things."
During his time with Barcelona between 2008 and 2012, Guardiola won 14 trophies, including three La Liga titles and two Champions League successes.
City are still likely to be without midfielder Fernandinho and forward Raheem Sterling for the return leg against Swiss team Basel at Etihad Stadium.
The pair are only just back in training after hamstring injuries but could be back in contention for Monday's Premier League trip to Stoke.
Fabian Delph could return at left-back against Basel, having served a three-game domestic suspension.
"We start again from zero. We have to be focused not to make a mistake - just be focused on what we have to do, offensively and defensively, to control the game and go through. That is the target," Guardiola said.
"Champions League games are something special and you have to be focused. Of course we are delighted with the result we have done [in the first leg] but in football everything can happen."
City have only progressed past the round of 16 once in their last six consecutive Champions League appearances, eventually losing to Real Madrid in the 2015-16 semi-finals.