People who do have ability and inability

Recently, I come to comprehend something. I deeply feel that if a person wants to have persuasibility, he/she really should have some professional ability instead of having his/her mouth.
Some people who really have ability to do something, they prefer to “do” by themselves; on the contrary, some people who are titular but inability like to “talk” more than “do”, in order to get the feeling that they are superior to others.
However, the respects are always given to the people who really have done something, and they don’t have to say, we can see what they have done. Compare with the others who are inability, they always like to brag about their status or contributions, being afraid that if someone didn’t aware of their deed.
I think I shouldn’t complain about it anymore, because this kind of people would still appear around us over and over again at every moment. What I have to do just to admonish myself against being this kind of people and to keep away from them.