What is desireless action?

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

Questioner: Acharya Ji, how will I get motivation to do some work, if I am not attached to the result of the work?

Acharya Prashant Ji: When you come to this hall, you are probably prompted by some desire, aren’t you?

Q: Yes.