You want to build processes and train people to take over the work you are doing to free yourself up to work on the next big challenge. This is the idea of making yourself completely replaceable. Except instead of being replaced, you move on to another area or another problem to solve.
Short term, you can do the work. Long term, it’s better to teach the man how to fish.
Some areas you can probably always deliver value:
Julie Zhou, The Making of a Manager