Disciplined thinking,
Disciplined systems,
Disciplined behavior,
Disciplined eating habits,
Disciplined fitness regime.
Disciplined working habits.
These are essential for living a good life.
One of these things here & there and your life goes for a toss. Like billions of lives out there.
Like one makes his muscles strong by working out in gym, discipline trains your mental muscles & makes you mentally stronger.
Once your mental muscles are stronger, you are in a better shape to make better decisions, think clearly, focus & do the right things.
Eventually leading to living a good life