The Catalan outfit regained La Liga from Real Madrid last season, but were thumped 7-0 by Bayern Munich over two legs in the semi-finals of the Champions League.
"In sport and in life, making rash decisions is the worst thing you can do. After our Bayern elimination, comments were directed at us to change everything. This always happens, especially in large clubs. You have to decide more quietly and then assess what you can improve and what you cannot," he told Sport.
"For example, the obvious case are Bayern. The lost two Champions League finals and then won in their third attempt with almost the same players. Sometimes change is not so necessary.
"The Barca team that won the treble with Pep Guardiola was not winning anything two years earlier and everybody wanted to change everything. Then they made history with almost the same team by adding Gerard Pique and Daniel Alves."
Fabregas has been linked with a move away from the club this summer.