With youth: Is willpower really needed?

The following is an excerpt from a samvaad (dialogue) session with Acharya Prashant.

Questioner (Q): Acharya Ji, how to improve willpower?

Acharya Prashant (AP): So, what has Aditya (the questioner) asked? “What can we do, to improve willpower?” Right?

What is ‘willpower’, and why do we need it? What is ‘willpower’?