Who is your poorest performing team member? Go with the first person that came to your mind. Now, what are you doing to turn that around or turn them out? Managers who last don't get the option of doing nothing. There are three things you can do that will make a difference.
First, You have to set aside time - regular, weekly time - to invest in that associate. It must become a priority. Second, when you meet with them don't talk (and certainly don't lecture) instead, listen. As the legendary Peter Drucker said about the most effective managers, "Listen for what is not being said."
Third, ask them "What obstacles do I need to remove that will help you succeed?" You are not obligated to do what they ask but you certainly need to know what they think their obstacles are. And, of course, remove them when you can.
Remember, your most expensive inventory gets in a car or truck and goes home every night. You cannot afford to ignore them.