Deserve before you desire!

Long time back, my Mama told me “Beta, deserve before you desire”. I was young and couldn’t understand what he meant. I recently said the same thing to someone else. I used the phase without knowing its depth. This post is an attempt to understand the phase I have been hearing from a really long time.
How do you know that you deserve something before you desire for it? I guess the cycle goes like this. First you desire for something then you try and figure out how much is the weight of that thing. Accordingly you decide what must be done to deserve it. Therefore, for deserving something it should first be desired for.
Next question, how do we know the value of a thing? What I’m trying to figure out here is how we ever know how much effort should be put into so that you deserve what you have desired for. I guess that’s why my cousins taught to take bribe. Ya, I agree, I take bribe from my family for every small thing I do. I’m the laziest person you’ll ever find and so I take bribe. I am proud to say that it works. At least for me, it works. They promise me a chocolate; I do the work and get it. I’m happy plus they are happy.
But how do you decide if the thing is more than just chocolates? If its something costly, if it’s about a person you like. How do you decide it? I never thought about it but now I know someone who thinks this way. It is new to me, as I have always been with people who either date multiple people at the same time or who just keep switching. But there do exist a really small number of people in my world who think before taking another step.
So is it at all correct saying them “deserve before you desire!”? I don’t have an answer but do hope to get it someday.