The deeper the river is, the quieter the water is. The same is for people and everything. The excitement and noise do not represent power, but silence and tranquility do not mean weakness and incompetence. .
A big talker is not likely to be strong and determined. On the contrary, a quiet person doesnt’t have to be someone who is not determined and doesn’t have his own perspective.
Similarly, a person who often shows off, or appears to be wise, talented is unlikely to be knowledgeable, more talented than a person who does not show anything.
Everything on the surface reflects only a very small part of the nature of a person or thing. So you should never rely solely on the outside to judge someone.