Whether it be to do your job, get your schoolwork done, clean your house, work on your creative passion, etc.
Bonus points if you’re someone without reasonable self-control so saying something like “I can only have a cookie after I do this/while I do this” doesn’t work for you and you’re just going to eat the cookie and not do it.
Motivation is a fleeting thing. Adulthood and success are built upon discipline, not motivation. We do what must be done, regardless of our feelings about it. Do what must be done, then enjoy your time spent doing better things once what is necessary is complete. Live by the words of Logan Nine Fingers from The Blade Itself:
It is better to do a thing than to live with the fear of it.