Insecurity and fear generate a tremendous amount of overthinking about matters big and small. When we’re not sure we’re doing it right, whatever it is, we can’t mentally move on, so we unintentionally leave the door open to overthinking. When we lack confidence in our own judgment, it’s natural—even, in a perverse way, useful—for our thoughts to repeatedly return to unanswered questions or unresolved situations, because our brains don’t like unfinished business.
