If you were trying to coax tiny, baby, scared puppies from behind the couch, would you yell at them? Tell them they're bad, wrong or worthless? If you were being strategic, you'd probably speak softly and gently to decrease their fear, making them much more likely to reveal themselves to you.
Working with feelings can be like coaxing puppies from behind the couch; they will often hide if they fear put-downs or stingy behavior. Helped to calm and relax they can more easily emerge and be dealt with. You can't work with what you can't see.