Drawing
Think of a person you love. You can picture them clearly in your mind. You would recognise them anywhere.
Why can you not draw them perfectly? I mean, pick up a pencil and try to draw the one you love... does it look like them? Would anyone else recognise them?
Why?
The brain has many independent parts. Our consciousness has access to only some of those parts. It is not easy to control your heartbeat... without practice. It is not easy to wire up the parts of memory to the parts of the nervous and muscular system in the hands.
Myriads of seemingly random connections have to be wired together to even throw a ball. But all it takes is practice and perhaps someone to help you along.

DCPU
If we had access to all parts of the brain what would we be capable of?
The parts of the brain allocated to speech are not contiguous, that is they exist at various places. The places can change over time, especially after a head injury. A different part of the brain will be allocated to learn speech.
This allocating mechanism is an interesting one, it is not a single part of the brain either, rather the frequency inputs all arrive in the brain and fall where they may. Repetition causes growth in brain cells, growth assigns brain matter to tasks. So it is a self-regulating system, requiring no central command unit.

Fastbrain
We know that the conscious part of the brain is very slow... probably because we have a habit of thinking in a language, which is a slow form of communication suitable for infants.
The subconscious is very fast. As tasks are repeated they are passed from the conscious into the fastbrain - the subconscious. We call it the subconscious because the actions it performs seem to be beyond our direct control, like breathing while we sleep.

Repetition
When we study for an exam we usually use repetition. This moves the knowledge from the slowbrain into the fastbrain.
Data that enters the fastbrain must be relevent, it is a self-optimising system, which requires clear pathways, otherwise misunderstanding results.

Understanding
Only when the fastbrain has obtained the knowledge it needs through repetition can understanding take place. Understanding can be thought of as intimate knowledge of a subject that is coherent with the other knowledge our brain has understood.

Lightspeed
For example: if we are taught repetitavely that light cannot travel faster than a certain speed ( c ), then everything we interpret will appear to obey that logic. When things don't make sense we invent other logics to try to maintain all knowledge in the fastbrain as being true and correct. Quantum physics is based on these incorrect assumptions about light and energy, inventing myriads of bizarre logics to explain away the inconsistencies from inaccurate understanding.

Our consciousness has many entry points into our perception, some operate simultaneously, some singular, such as when we dream.
We store collected frequency readings and call it data, pictures, sounds, sensations. It is all the same thing. We call some frequencies colour, some pitch, heat, smell, but they all exist in a vast rainbow of energy that we have a little awareness of.

Once we understand the potential nature of all matter, we get a clearer understanding of the universe, without the clutter of interpretation through conscious dissection.