In my personal experience my mental state dictated how well I could control my stutter. In my teenage years I was very confident and socialized often which resulted in me not stuttering very often if at all. I’m 31 now and I don’t feel confident and also home majority of the time. I stutter almost every day. I know I can improve it but I guess I’m just comfortable currently. I also think therapy is beneficial for us since a lot of people who stutter are in their heads a lot which can be a bad thing depending on your thought processes