Seems sort of arbitrary to me? There are a million things we don't have control over, and speech can be one of those things. Working to accept the lack of control and find an understanding of how to work in discomfort, as opposed to exerting limiting control (and avoidaing discomfort, which is part of life) onto your circumstances seems generally more functional to me. Accepting discomfort in this way is really what led me to where I am now with my speech (covert stuttering).