Your life should never be the same as it was the day before. Your routine may stay the same, but the way you do it and the way it affects you shouldn’t be.
For example, you spend 15 minutes every day learning a foreign language—but no two days of learning the language are the same. On one day, you knew less, and on the next day, you knew more. You are progressing, and there’s no consistency in progress other than the rate at which you improve. Don’t let consistency restrain you from new experiences, either. I’ve seen you turn down great opportunities to pursue a project or work later only to go to sleep because you had to stay consistent. It can be argued that you can continue the work in the morning or wait for another day to pursue the project, but why do that when you have the vigor and excitement to do it now? Build flexible time into your life.
That way, you won’t find yourself in a state even resembling stagnation.