Trust direction

The right direction of a trust can be simply explained with an analogy. Suppose that a friend wants to borrow your car; you share your keys to the car with them and then you give them permission to use the car.

In terms of the Active Directory trust, the friend will map to the user account, the car to a resource, and you will be the resource owner. The trust flows from the resource to the user. The admin of the resource has to create the trust.