Willpower is a finite resource. The research on this is overwhelming and the lived experience is universal. The morning version of you is decisive, energetic, and committed. The evening version of you, after a day of decisions, is irritable, tired, and prone to giving in. Every diet that fails fails in the evening. Every quit attempt that breaks breaks at night.
A Sikh framework does not depend on willpower to deliver discipline. A Sikh framework depends on routine. Built once, defended for a season, lived for life. Routine continues working when willpower is gone, and most of life happens when willpower is gone.