A sustainable pace defeats heroic inconsistency over enough distance.

Over any real distance, the moderate pace you can hold beats the intense effort you cannot. Bursts followed by collapse produce less total progress than steady work, and they also produce the sense that you keep failing, which erodes the willingness to start again.

Set the level you could maintain in a bad month rather than a good one. It will feel too easy at first. That feeling is what makes it survivable for years.