1. People you trust with your life. They'll risk a bullet for you, possibly jump on the grenade.

2. People you trust with your wife. Deep personal trust, like telling them that you're gay (or homophobic) or letting your kids stay with them.

3. You trust them because it's in their best interest. They won't screw you because it screws them.

4. Competence. They trust themselves.

1 and 2 usually don't overlap with 3. They're not necessarily different levels. You can trust someone with your life, but they may be incompetent and think your trust is misplaced.

We have great hiring, so all full time colleagues are at category 1 but rarely 2. Contractors are usually at category 3. Some contractors are good bros but you

My most costly mistakes was neglecting category 4. Competence isn't a boolean; it's levels. Someone highly competent in a past task can be incompetent for a different task, esp. Peter Principle.

I used to freelance. The majority partner would lose say $50k and I'd lose $10k on a failed deal. The deal was easy - it was signed, practically done, just not paid. And too often they failed to get payment. They pulled through category 3, sometimes 1, but not 4.

There's the saying of "never attribute to malice what can be attributed to incompetence". But very often competence is the more serious breach of trust. You can trust a crook with the right incentives, and in very big organizations, most of them will be crooks.