Trust is an emotional brain state, not just an expectation of behavior. Of course saying this suggests that trust is expected by human beings in many ways. Maybe people don’t just trust everyone in their life (good advice by the way) but trust is a central part of all human relationships, including romantic partnerships, family life, business operations, politics, and medical practices. Sooner or later we all have situations where trust is expected and needed. Friendships are built on two things, respect and trust. Both parties need both respect and trust for it to work.
“I don't trust people who don't love themselves and tell me, 'I love you.' - Maya Angelou
There is an African saying which is: Be careful when a naked person offers you a shirt.” ― Maya Angelou