The same is true for the martial arts. Many students (and I count myself as a student even after 45 years) think they can skip some classes, shop around schools rather than immerse themselves in one school/system, or only practice at the dojo. We think we are better than we really are.
Without the eyes of a qualified instructor our technique and form slips away and we slide backwards in our skills.
The fix is simple; get your butt to a dojo/gym and give yourself over to a certified instructor, then work said butt off as you strive for, if not perfection, at least competency.