A large part of the concept of habitus is that it brings attention to the fact that there are limitless options for action that a person would never think of, and therefore those options don't really exist as possibilities. In normal social situations, a person relies upon a large store of scripts and a large store of knowledge, which present that person with a certain picture of the world and how she or he thinks to behave within it.
A person's habitus cannot be fully known to the person, as it exists largely within the realm of the unconscious and includes things as visceral as body movements and postures, and it also includes the most basic aspects of thought and knowledge about the world, including about the habitus itself.