"There is no greater slavery than saying yes when you want to say no", Baltasar Gracián.
It is intimately related to rejection, and when it escapes from our lips, it has the capacity to turn us into real villains in the eyes of others. But paradoxically, it is also the particle that allows us to establish limits, mark distances, adjust our tempos and respect our needs. And on too many occasions, it costs us horrors to verbalize it.
Knowing that it is not a skill that is known as "assertiveness". The more assertive we have, the greater the security we have in ourselves. How is an assertive person? Well, it is someone who knows how to express their wishes in a kind way, respecting whoever is in front of them and always being direct, nothing of going around with detours.

"Neither submission, nor aggressiveness, balance is assertiveness".

-Riso Coma Walter-.

With all this, it is not about becoming selfish people who ignore the needs of others. It's about knowing how to find a balance between two equally bad extremes: always say yes and always say no.