When you are the boss, sometimes you can have to spend time on problems that could be solved by someone else.
This interferes with your own schedule and can give you less time to complete the tasks that you need to. It can also interfere with the time that you have with your family if you are getting calls when you are away from the site.
If you train your employees to only call you with problems that only you can deal with, then this will solve a lot of these issues.
Your employees should be trained to deal with both routine problems and some that may be unforeseen.
They should work together to solve any routine problems that may occur.