Since many of my readers are not from the United States, I should say that  in 2/3 of the world the individualistic notion of assertively expressing our personal needs is not accepted practice.  Most Asian, South American and African cultures value group needs above individual needs, and frown on  direct self-expression.   Direct confrontation is considered rude.  Instead, they tend to use face-saving avoidance and nuance.   The ultimate insult is to attack one’s family or group, not to attack the individual.  In contrast, European and North American cultures tend to be much more direct about their personal desires.    Advocating for individual needs above the needs of the group is accepted practice.  Even within the United States, there is considerable variability, however.   My impression is that New Yorkers tend to be very abrupt, while native sourtherners tend to be less direct in their communication. Even within regions, some will be more assertive than others.