It has been long known that maturation and self development occur in waves. A person may invest much effort learning and developing themselves without seeing any results only to find that at some future point they had been lifted to a completely new level.
In Kabbalah, the subconsciousness is compared to a womb. A womb can be closed, such as when a fetus is developing within it, or it can open, as at the point of labour and birth. As one learns a new skill he plants it in his subconsciousness so that it becomes a part and parcel of his being. Sometimes the subconsciousness responds quickly and we clearly see our progress. At other times, however, we may invest immense effort at progressing yet our attempts seem futile. It is as if our subconsciousness is not receptive.
In truth, however, all of our efforts to develop ourselves impregnate our subconsciousness, only sometimes, especially when the skill we are attempting to develop is novel and complex, our seed remains hidden within the subconscious womb and undergoes gestation. Then, unexpectedly, we discover that we've leaped into a completely new level in skill performance. This is where the subconscious womb opens.
I experienced this phenomenon profoundly in my attempts to learn how to skateboard. In the first few weeks of skating I felt gradual progress. Soon after, however, I reached an impasse, where I felt that I couldn't progress any further. Thank G-d I persisted in my efforts and one afternoon at Praharn skate park, my inner womb opened and I felt an immense increase in energy and proceeded to perform several tricks which I couldn't execute before.
The message here is quite clear. Sometimes we perceive the fruits of our labour immediately, and sometimes we perceive them only after some time. But regardless of our perception, the fruits are always developing within, we need only persist patiently.