In Buddhism, the first noble truth is that “all existence is dukkha” with dukkha usually being translated to suffering. But can also be understood as being incapable of being satisfied. That while there is the “common” suffering of old age, illness and death, there’s also this yearning or craving for more that we can’t satisfy.
“Reality is merely an illusion, albeit a very persistent one.”Albert Einstein
We keep having these expectations and these hopes. We expect that this new shiny thing will bring us happiness, a new game, a new car, a new “thing”, a new relationship, a promotion, a bigger house, a vacation, etc…
But it never does. We’re always wandering and craving for these impermanent things and transitory states that are ephemeral. We continually grasp at the shadow of happiness, and are left disappointed.