It is difficult to start a car on a steep up-slope. On a geared car, you would have to switch to the most powerful gear and your clutch release has to be timed just right.
It is easier to start a car downhill than uphill. In the western world, it is easier to develop a running or cycling habit during the warm summer months and sustain this momentum into the winter (while the opposite is true near the tropics). It is easier to develop a reading or a meditation habit during a long vacation than in the midst of one’s routine.
A habit is like a rolling car. The hardest part is getting started. How can we make that easier?