Junior leaders treat business needs as fixed, and their own capacity as flexible. Experienced executives treat business needs as flexible and their own capacity as fixed. Math you will actually use. 2021-11-03. Melissa & Johnathan Nightingale. article 
**The thing junior leaders get wrong is that they treat the business needs as fixed, and their own capacity as flexible.**
When the business asks for something, a junior leader says "yes," instinctively. Because every request is an opportunity. An opportunity for visibility, for growth, for (ahem) Executive Face Time. When you're in this headspace, opportunity feels like a scarce resource. You have to say yes to everything that knocks on your door because you're not sure it'll come around again. You say yes even if you're already underwater.
**The thing solid executives know is that most of the time, business needs are flexible, and your own capacity is fixed.**
That opportunity is less scarce than your ability to effectively seize it. And that saying yes to too many things means fucking most of them up. You have a number of hours in the day or week that you can give great work to. Past that point, your work gets shitty in a hurry. Past that point, you fall into the anxiety, self-doubt, and racing to catch up. Past that point you're fighting math.