First, a good supervisor must have excellent people management skills. He or she should be able to assign the right person for the right job. This requires ability to judge a junior’s strengths and weaknesses and provide him right opportunities to enhance his strengths and overcome his weaknesses.
Secondly, a good supervisor should have in-depth knowledge about his functional area. This is essential so that the juniors inculcate respect for their bosses. For e.g., you will not be able to look up to a supervisor who knows less than or just as much as you do.
Thirdly, a good supervisor should be good at communicating and influencing. This is an important quality because knowledge or information alone is not useful until and unless it is effectively communicated. A good supervisor should be clear and assertive in his instructions to the juniors. For e.g. many mistakes are committed by juniors because of communication gap or ambiguous communication from their bosses.
Fourthly, a good supervisor knows how to keep his team motivated. Intelligent use of rewards and recognition is necessary to get the best out of a team. A good supervisor knows what motivates each individual and uses that knowledge to lead each one into delivering his best.
Lastly, a good supervisor uses delegation judiciously so that both the junior and supervisor are benefited. Juniors get a sense of empowerment while taking up more responsibility and at the same time, work load on the supervisor is considerably reduced.
In short, a good supervisor is a good leader. Equally important is that he should be an approachable person who puts his juniors at ease and listens to their ideas, suggestions or pain points carefully. This, I believe, is the perfect recipe for an ideal supervisor!