Not doing something will always be faster than doing it. This statement reminds of the old computer programming saying, “Remember that there is no code faster than no code.”

We agree to many requests not because we want to do them, but because we don't want to be seen as rude, arrogant, or unhelpful. Often, you have to consider saying no to someone you will interact with again in the future.

Saying no saves you time in the future. Saying yes costs you time in the future. No is a form of time credit. You retain the ability to spend your future time however you want. Yes is a form of time debt. You have to pay back your commitment at some point.

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Saying no is an important skill to develop at any stage of your career because it retains the most important asset in life: your time. As the investor Pedro Sorrentino put it, “If you don’t guard your time, people will steal it from you.”

Upgrading your no doesn't mean you'll never say yes. It just means you default to saying no and only say yes when it really makes sense. To quote the investor Brent Beshore, “Saying no is so powerful because it preserves the opportunity to say yes.”

This is similar to the well-known “Hell Yeah or No” method from Derek Sivers. If someone asks you to do something and your first reaction is “Hell Yeah!”, then do it. If it doesn't excite you, then say no.

More effort is wasted doing things that don't matter than is wasted doing things inefficiently. And if that is the case, elimination is a more useful skill than optimization.