What is the 21-90 rule?

The 21/90 Rule Explained

The 21/90 rule suggests that it typically takes 21 days to establish a habit, while 90 days are necessary to transform that habit into a lasting lifestyle change. Are there any new lifestyle modifications you wish to pursue? By committing to your goal for 21 days, it will evolve into a habit. If you maintain that commitment for 90 days, it will seamlessly integrate into your lifestyle.