https://80000hours.org/articles/dont-follow-your-passion/
80,000 Hours is a nonprofit organization providing free resources to people to find best opportunities to have a positive impact on the world. I think that if one's occupation has a clear positive impact on others, it is easier to get excited about doing it (and doing it well).
One of three important aspects to life/work satisfaction (and motivation), according to the well-researched Self Determination Theory is "relatedness" - feeling like you're contributing to welfare of others (see https://en.wikipedia.org/wiki/Self-determination_theory ).