Learning a complicated ability like dancing west coast swing is not a linear process. Your learning will go through a cycle of mastery, in which you learn a concept and then repeatedly come back to it in different and more advanced ways.
To take an example, let’s say that you learn about the concept of rolling through your feet. After a lot of practice, you finally develop the muscle memory of rolling through your feet on all your basic movements.
A while later (it might be a few months, or it might be years), you realize that you can use this technique to adjust your spacing with your partner. Instead of changing your footwork on a tuck, you can control your roll through the feet in order to match the degree of compression offered by your partner. Suddenly you see dozens of opportunities to apply this technique—in tucks, whips, hip catches, throwouts, and more. Back to the practice floor.
Even later, you realize that you can make your dance look more legato or staccato depending on how quickly you roll through the foot. Again: more practice time.
The point is that a relatively simple dance concept can be applied in many ways, and part of learning the dance is discovering new places to apply the fundamental concepts in more nuanced ways. Someone who has just learned to roll through the feet in basic patterns can legitimately be said to have learned to roll through the feet, but that doesn’t mean there is no more to learn. Usually, the “more” only becomes apparent when other elements of the dance have become more developed, and then it becomes productive to revisit the old ideas in new ways.
This is the cycle of mastery: learn a concept, apply it, then come back later and apply it at a higher level. It can be frustrating if your attitude is “I already fixed this—why is it broken again?!” But, if you take the attitude that now you can do even more with the concept than you used to be able to, then it becomes clear that you are making progress.
The implication of the cycle of mastery for practice is that you should make it a point to periodically revisit your core technique elements. When you do, your goal should not be to merely clean up what you did before. Instead, seek to find new ways to apply the same concepts. As you grow as a dancer, you should discover more depth to the seemingly “simple” technique elements that you learned as a beginner.