We value very much our variety and uniqueness. In general, almost every human is proud of their unique qualities. I hear that, when humans talk to aliens, it is considered impolite and strange talking about your personal qualities, but is considered ok by aliens to speak about unique qualities of your specie. This is a new thing for us. Often, in conversations between humans speaking of self becomes a bit impolite, but in general, humans often speak of their own specifics and preferences. It is very polite to ask a human about their own preferences and interests. Friends very often speak about their own qualities. Lovers almost always speak of their own specifics, especially at the time of familiarizing with each other. Sometimes, people don't share with others some of their individual preferences, mostly because they may not trust others and sharing extra information might harm them. Irony, sarcasm, and negative humor are frequent between humans and people often avoid sharing too much with strangers because they fear being laughed at. Almost all people are afraid to look stupid, so they avoid taking risks when speaking. Many often would prefer not to say anything, than to say something potentially incorrect and be caught in incompetence.