Opportunity cost is an important business concept that often affects how leaders make decisions.
When you say yes to anything, you are explicitly or implicitly saying no to something else. Every resource allocated to one initiative is a resource unavailable for another.
The best leaders I have worked with are acutely aware of this trade-off. They don't just evaluate whether a project is worth doing — they evaluate whether it is worth doing instead of everything else they could be doing.
This is especially critical in technology leadership, where the backlog of potential initiatives always exceeds available capacity. The discipline to say no to good ideas in favor of great ones is what separates effective CIOs from the rest.