Pleasure vs. Satisfaction
Pleasure is a transitory feeling. It persists only as long as those conditions which produce it survive. Satisfaction is an enduring state. Once a need is fulfilled, it is extinguished.
Eating a fine meal pleases the senses while satisfying a biological need. But biological needs are in the baser realm of human experience. The ability to procure, prepare and provide a meal has meaning beyond each instance of the act. All the steps may not be pleasant, but in them we find satisfaction.
Similarly, volunteer work is only sometimes pleasurable. But the satisfaction that comes from working with and for things larger than the self outlast any suffering endured in service.
H/T: ChicagoBoyz commenter “Joseph Somsel”