Happiness will never come to those who fail to appreciate what they already have.The author of this saying is quiet right. When a person dreams about some game console, for example, he is imagining how happy he will be when he has it. After some time since that person had bought the game console, he is, actually, not as happy as he had been imagining before he bought the game console, and he wants more... Eventually, that game console stop being something special for this person, it is beginning to be something ordinary.
Imagine that one day he loses that game console... and then he will be so upset, that he himself will be suprised, because in the past, when he had his console, he didn't suspect that his loss could be so offensive; he didn't suspect it would be so pity to lose.
We all should try to cherish all we have. Most people just don't appreciate things they have, and they would be very upset if those got taken away.