Most managers are either busy, or not there. That makes it hard to do business with them. How many phone calls does it take to reach you if you can be reached at all? Personally, I have other people do incoming phones for me, so I am reachable by email only, unless you are someone who it is necessary for me to communicate with directly. I just have too much to do. If I answered insignificant phone calls about tiny issues all day long, I would have no time to handle bigger issues. Big things get priority with me.
But, if you are in management or sales, then client acquisition should be your biggest priority, with on-time delivery being equally important. If your schedule is booked too tightly, you will not be able to handle last minute phone calls that come in. You will not be able to deal with unexpected problems. The point is to be available just in case something important comes up.
Warren Buffet likes (this is based on a book I read 12 years ago) to have about two hours of work per day. The rest of his day is open just in case he needs to attend an unexpected meeting, or has an unexpected problem. He leaves himself open. The rest of the world does the opposite and is always too busy to deal with anything.
To have more free time, that means you need to hire more people, and more reliable people. It is not easy finding people who can handle their work perfectly with minimal or no intervention (as Warren Buffet likes). But, if you plan on having a more open schedule, so you can do a better job being available for bigger concerns like last minute new clients, meetings or unexpected problems, you need to be better at delegating. Farming out work to others is a very complicated skill. But, to make it higher on the food chain, it is one of the most important skills that you can master!
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