I saw something sad in the park this morning. A boy was trying to learn to ride a bicycle, but I could see that he never would - not with his present approach. Why? He had one training wheel, and the bike was leaning about 15-degrees off vertical as he struggled to use the bicycle as a tricycle. I could see that the metal arm that supported the training wheel was starting to bend from the strain - thus making the lean ever more pronounced. [Incidentally, with two training wheels, I think he might rapidly learn to ride because he'd experience tipping from one side to the other, through the balance point.]
I've told yoga students before that there are three timelines for learning inversions (upside-down postures, which all require one's body to learn to balance 180-degrees out of phase with the balance we all mastered as toddlers.) The first timeline is if you are willing to learn break-falls (i.e. how to safely land when - not if, it will happen - one loses balance.) If so, one can learn any inversion (that one is otherwise physically capable of performing) in an afternoon. Second, if one gets near (but not up against) a wall, and only uses the wall when one is falling towards over-rotation, then one can learn the inversion in a month - give or take. Finally, one can lean up against the wall for a million years and one will not spontaneously develop the capacity to independently do the posture. Why? Because one's center of gravity is outside one's body, which means one is in a perpetually unstable state, and one cannot stabilize into a balanced position from a state of falling (and leaning is just falling with a barrier in the way.)
Finding balance requires that the body be able to adjust toward any available direction to counteract the beginning of a fall in the opposite direction. I was fortunate to have studied a martial art that required learning break-falls from the outset, this made learning balances (not just inversions, but also arm balances, standing balances, etc.) much easier because there was no great concern about falling. I knew my body could fall without being injured.
Without falling there's no learning balance, and if you only fall into the under-rotated position, you are still not learning to achieve stable balance. At some point, you will need to experience the dread fall towards over-rotation.
Time to ditch the training wheels.