This is despite of all circumstances quite often topic involved in most cases. We can't classify this factor as source of the issue, it has tendency to be as accompanying symptom. Most of the clients see on the first stage this topic, later it is recognized as result of something certain what is important in whole therapy. This is why the first consultation is important, where is founded core issue.
Rare is when the topic is really self-confidence, this is dependent on individual circumstances but generally we can say that is important to work on self-image, very often individuals with low self-confidence has problem to express own feelings, it is replaced with behavior patterns as part of defense mechanism. When we talk about patterns, it is meant also language patterns, for instance that is not used direct communication and some expressions replacing ability to express feelings. For instance to the question: "How are you?" the individual answering: "I'm fine, of course." Phrase "of course" is likely indicator of defense mechanism.
This probably will sound incomprehensible but in our daily habit we use phrases such as "How are you?" "I'm fine, thanks." In certain cases these phrases can be learning tool for subconscious how to disconnect inner self, more precisely own feelings. Use this phrases is completely fine if we have intention to listen and say what we feels or some happenings.