Why would you engage in self-discipline if you believe it is all for nothing? For somebody who struggles with doubt, low self-esteem, or insecurity, self-questioning can be a debilitating factor that goes well past the point where introspection remains valuable. “I don’t know if I can do this,” “Am I doing this right?” “What’s the point of this, anyway?” “What the heck is this?”—all these questions serve as barriers to disciplined action.