Brain authorities (sounds like something out of science fiction, doesn't it?) recognize that each half of the human brain leads in different areas. The right brain or creative brain conceptualizes space and distance perception, drawing and visualization.
The left brain's intellect is mainly responsible for the seat of human logic, words, facts, our semantic pieces of information. It is when the two sides of the brain receive contrary instructions that the athlete, including the pool player, may be misled, especially if the visual picture, not the logical, is lacking.
Imagine you stand over an important break shot in Nine Ball. You are internally verbalizing your wishes, including "I'm going to break the 9-ball in!" and "Hit this one hard!".
At the same time, (our two brain sides can each operate at once) you are a bit concerned about scratches you've taken through the day in the right hand side pocket. You can almost see a recent embarrasing scratch.
Your eyes lock onto the rack before settling in to stroke the cuestick but you can almost feel that side pocket burning in your peripheral vision. The right brain sees all in reverse, so your verbal wishes become an unhelpful "!ni llab-9 eht kaerb ot gniog m'I" and "!drah eno siht tiH" accompanied by with a clear visual picture, a full color remembered illustration worth 1,000 words, of the side pocket.
If you ever played much at stick-and-ball sports, you know what will happen next. The cue ball pops directly in the side and ends the hopes you had with impunity. You complain, "I knew I was going to miss!" as you foresaw the miss as a key visual element, a right brain picture.
The struggle to get better at pool is the struggle to define positive mental pictures. If you know that battle, and recognize it's not about pool stroke technique or pure hand-eye coordination, half the victory is won. What is the champion's mindset at the table?