We can breathe, eat, walk, sleep, work etc. etc. for quite some time without paying much attention to it, so it seems we're having pure non-verbal, uncommented experiences of said activities. Of course, when illness, aging and dying strike, and the other not so fancy forces of living life, things can change. For example, if one gets pneumonia or malaria, or even just the common cold, the way one breathes makes a world of differences in how adversely affected one will be and feel by the disease. And to change one's breathing, requires quite a bit of thought and skill, definitions and practices. Or, we can usually walk just fine without giving it much thought - but wait till you stumble or have to move around with an injured leg. Suddenly what used to come so naturally, as such a given, becomes a matter of conscious decision-making and acting with precision. And the more one trains oneself in these things while one is still relatively well, the fewer troubles one will have later, when having to deal with aging, illness and death.