When there is no agreed direction, every marketing decision becomes a debate. Agencies produce work without a coherent brief. Teams produce activity without a coherent logic. Money gets spent on things that feel right rather than things that are right.
A strategy does not end all disagreements. But it gives the business a basis for making decisions that is grounded in evidence rather than instinct, and it gives everyone: your team, your agencies, and your leadership, a shared direction to execute from.