Andrew S. Grove
Your job as a manager is not to do the work, but to maximize the output of your organization by acting as a systems engineer and a multiplier of your team's efforts.
You must treat your organization like a manufacturing plant by identifying the limiting steps in your workflows and creating leading indicators to measure both the quantity and quality of output.
Because your time is a strictly finite resource, you must relentlessly focus on high-leverage activities where a brief interaction or decision significantly impacts the long-term productivity of many others.
Meetings are not a distraction from managerial work but rather the essential medium through which information is shared, decisions are driven, and cultural values are transmitted.