I have a bad habit of assuming what someone is thinking or feeling during a conversation. This usually leads to me believing they are uncomfortable or they think I am stupid or they are trying not to laugh. Which in most cases is not true, but it ends up destroying my self confidence during a sentence and causes my stutter to get massively worse. I've also noticed this when telling a joke. If I let it come out naturally, I'm usually pretty fluent. But if I'm thinking, "they're gonna think this is really funny" or something along those lines, I tend to put way more pressure on myself which makes my stutter worse. This usually turns into a self hatred sort of thought that, once again, makes everything worse. Bottom line: it's better for me personally if I don't assume what someone is thinking or feeling.