You catch yourself doing something and you can't quite say why. A flinch when someone with a certain accent enters the room. The reflex to step aside for a man in a suit. A flash of jealousy at a friend's promotion before you've registered the news. The reaction arrived before the thought. You weren't deciding. Something was deciding for you.
K wasn't impressed with the unconscious as a metaphysical category. He treated it as conditioning that hadn't been looked at yet. Not a separate room of the mind. Not a Freudian basement. Just the parts of your conditioning that the part of you that calls itself "me" hasn't walked in to see.
Make the move and the basement empties. The flinch is a learned reaction you never noticed installing. The flash of jealousy is the comparison engine running below your attention. The reflex deference is the family rule about authority figures, still in force. Bring attention to any of it and it stops being "unconscious." It's just conditioning, being looked at.
The looking is uncomfortable. There's a reason the basement stayed dark. Walking in means seeing that the responses you thought were "just how you are" were small assembly lines of training. The "me" loses some of its mystery. It looks less like a soul and more like a cabinet of inherited habits with the labels worn off.
Most of what people call the unconscious is conditioning the conscious mind would rather not own. The wall isn't between consciousness and depth. The wall is between the looking and the not-looking.