[W]e are more likely to self-handicap if we “have a precarious but not entirely negative sense of self-competence.” Put another way, if we lack confidence about our abilities we err on the side of caution and sit on the fence of our own potential.

Self-sabotage comes in many forms.

It’s when we do everything, but the one thing we need to do; it’s when we pick a relationship apart because things are a little too perfect; it’s when we polish off food when we’re well beyond full and it’s when we drink or drug ourselves into a stupor to subdue emotion; it’s when we go on shopping sprees we can’t afford; it’s when we curl into ourselves in anticipation of rejection; and it’s in the lack of too much effort lest we fail and confirm our fears.

Sarah Berry, Self-sabotage: failure’s fatal allure