The Eisenhower Matrix
Attributed to Dwight D. Eisenhower · 1954
"Tasks fall into four categories along two independent axes — urgent versus not urgent, important versus not important — and most people's schedules are dominated by the urgent-but-unimportant quadrant, which crowds out the important-but-not-urgent work that actually compounds."
"What is important is seldom urgent, and what is urgent is seldom important." The line attributed to Eisenhower is the entire matrix compressed into one sentence.
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80/20 Strategic Planning
"Most underperformance isn't from doing too little — it's from spending time on the wrong 80% of tasks, so applying the Pareto principle deliberately to planning (identifying and prioritizing the 20% of actions that drive most results) outperforms simply working harder or longer."