Shyness - as a sign to the interlocutor that you can be used
In modern society, there is such a situation that being arrogant is not fashionable, even shameful. But being modest and shy is cool. Nothing like that. If a person is modest and shy, it gives a signal to other people: "He is Weak. It can be milked!".
It is not necessary to be arrogant all the time, but when your interests appear at the point of contact with the interlocutor, then it is not up to embarrassing, you need to give and get a result.
