I guess it is a desire in one's heart to get what they do not have.
It can be a good thing if you see it in another way. For example if you want to drive a car, then you will be driven the desire to learn how to drive. After that, you will aim to save enough money to purchase a car. This sort of wish for thing will be a kind of motivation of doing something in order to get what you wish for.
I find in life we do need to fire up our desire of wishing for things that even though you do not have. It will help you to work in the right direction of getting it.
That is what I teach my kids when they want something, they have to work for it. Like when they are schooling, I told them that I will buy the toy they wanted but they must show me results in their studies.
It helps to motivate them to study and achieve the results that I had asked before they can get what they wanted.