There is one thing I always try to remember when managing groups of people. That 1 thing is that I am there to ensure that they can do their jobs successfully, not so they can make my life easier. This means finding more efficient ways for your employees to complete tasks, standing up for them (when possible) and genuinely seeking feedback to enhance yourself as a supervisor.
Are you creating opportunities for your employees to grow (be it through training, mentorships, seminars, etc)? Do you manage the workloads you are placing on your crew? Are your directions clear and concise?
At the end of the day, you are only as good as the employees that work to support you. It is up to you to engage, support and be a true leader.
If you would like help in supporting your group, email me @ email@example.com.