Let your goals expand your usefulness.

A goal can grow you or just enlarge you, and the difference is whether it increases what you are able to give. Aims that expand your usefulness tend to keep you engaged, because there is always another way to be useful, whereas aims that only expand your standing arrive at a ceiling and leave you wondering what the point was.

Take your main goal and ask what it would let you do for others if you reached it. If the answer is thin, consider adjusting the goal rather than abandoning it. Often a small change of angle keeps the ambition intact while giving it somewhere better to go.