Smith, an employee from an IT company perceived himself as the best programmer among his fellow colleagues but when his boss test his skills the result of his answered test was unexpectedly low. Smith's pride was hurt and described his boss as bias despite the fact that he could not explain the meaning and the possible outcome of the codes shown in his test. This scenario is an example of the Dunning-Kruger Effect. We are like Smith, thinking we are better than most average people and which makes us incompetent. We have this Illusory Superiority, overestimating our intelligence despite the lacking experiences or expertise in any discipline ranging from leadership skills, ethics, logic, emotional intelligence, humor, etc. In fact, incompetent people lack the skill of recognizing their own incompetence. While the competent, having a moderate amount of experience or expertise tend to have low self-confidence in their abilities. They know there is a lot of things they do not know and assumes everyone is knowledgeable too. If they find a skill easy they assume others can too. They do not perceive their abilities as special and everyone can learn their acquired skills.
However, illusory superiority has an advantage, it acts as a protective mechanism for incompetent, shielding their self-esteem from depression. So thinking you are better is good for mental health. But it would be better to humbly ask and accept the evaluation or constructive criticisms from other people for better self-insight and improve the lacking capabilities. To be real smarty pants, you must learn to recognize your own faults then learn from them and never stop learning. It is better to commit a lot of mistakes than being always right because we learn a lot from failures than successes. But please do not use this advice as an excuse to act immorally.