Fulfilled desires, like pleasures (even of the intrinsic kind), are states of achievement rather than default states. For instance, one has to work at satiating oneself, while hunger comes naturally. After one has eaten or taken liquid, bowel and bladder discomfort ensues quite naturally and we have to seek relief. One has to seek out pleasurable sensations, in the absence of which blandness comes naturally. The upshot of this is that we must continually work at keeping suffering (including tedium) at bay, and we can do so only imperfectly. Dissatisfaction does and must pervade life. There are moments, perhaps even periods, of satisfaction, but they occur against a background of dissatisfied striving. Pollyannaism may cause most people to blur out this background, but it remains there.
~ David Benatar