It is, however, an incomplete idea. This is especially true in a field where absolute perfection can't be attained — a field such as learning.
The idea that we will always be imperfect may be depressing to many people but I believe the idea can keep us intellectually humble. It will also keep us asking questions and engage our inherent curiosity.
All of these are wonderful things so if you want to keep learning try unlearning the idea that "practice makes perfect" and instead practice recognizing those areas where you are still imperfect. Counter-intuitively, it may get you a little closer to your goal.
To this end, I recently came across a story that said Amish quilters purposely sew one imperfection into their quilts to serve as a reminder of their own imperfection.
What serves as your reminder?