Dan Olsen's inversion of Spider-Man's line ('with great power comes great responsibility') into 'with great responsibility comes power' — a description of the PM's position: PMs are held accountable for product outcomes and strategy without having direct reports or formal authority over the people who build the product.
The implied practice is that PMs get things done through influence and persuasion rather than authority ('bring the donuts for the engineers') — buy-in on strategy is earned, not mandated. Related to Misconception: PM Owns the 'What', Engineering Just Executes the 'How' and Signing Up for Outcomes vs. Feeling Responsible for Outcomes.
Dan Olsen states the tension bluntly: a PM is responsible for a product's success but "with great responsibility comes no power" — no direct authority over engineering, design, or the rest of the team. His resolution is that a PM's real leverage comes from owning the problem space (see Problem Space vs. Solution Space): by rigorously defining the customer and their problem before anyone proposes a solution, the PM earns influence that formal authority doesn't grant. He calls this the PM's unique value-add, distinct from prioritizing or spec'ing features.