If you can't play office politics then you can't get the leverage and context you need with which to improve the product. Office politics is table stakes for a manager. Why? Because a company is thousands of people and dozens of divisions which each have different goals. Office politics is how you make sure that what you want fits in with what everyone else wants. Blindly trying to improve the product without taking the rest of the company into account is a recipe for disaster.

edit: The worst companies are the ones who claim they don't have office politics (ie: we're a flat meritocracy) but instead simply make it hidden and much harder to understand.