Where does your drive come from? What pushes you on to complete your goals? I’m not asking because your examiners necessarily will want to know, but because I think it’s good for you to bring it front and centre for yourself.
Is it for personal achievement? Is it for a career? Is it to make someone proud? Is it to be the best? There’s no right or wrong answers, just a source of energy.
The PhD is supposed to be difficult. Your motivation can help move you beyond the difficulties. Doing things can get so intense that we forget why we’re doing them in the first place. So take a step back and put that motivation at the front.
Why are you doing this? OK, now do it.