Aggression
It is sometimes said about assertive behaviour is that it involves being aggressive. Assertiveness involves clear, calm thinking and respectful negotiation where each person is entitled to their opinion. Aggression involves bottling up feelings which eventually explode, leaving no room for communication.
Some people think that being assertive is about being selfish, it is in fact the opposite. Assertiveness is about acknowledging all opinions as important. An assertive attitude says "I matter and you do too". Learning how to express yourself assertively can seem difficult at first but you can develop the skills of assertiveness.
