Putting junior people in charge makes them better. It makes them understand what is going on above their pay grades and how their jobs tie into the mission.
It is one of the best possible ways to develop junior team members to become not only better at their jobs but better leaders in the future.
Teaching humility, confidence, and creating high-level team players are only some of the areas where putting people in leadership positions is helpful. Leadership is a tool that can help you help your people. Use it.