Importantly, Wolpe believed that these techniques would lessen the anxiety producing association. Assertiveness training proved especially useful for clients who had anxiety about social situations. However, assertiveness training did have a potential flaw in the sense that it could not be applied to other kinds of phobias. Wolpe’s use of reciprocal inhibition led to his discovery of systematic desensitization. He believed that facing your fears did not always result in overcoming them but rather lead to frustration. According to Wolpe, the key to overcoming fears was "by degrees.