Practice Makes Permanent
I played basketball as a kid, and during the summer would always go to basketball camp. Sander Scott was a really good high school and collegiate basketball player from Michigan, and he put on a camp for several summers. I attended his camp, and we worked on dribbling, passing, shooting, and all the other fundamental skills of the game. There were always so many skills to work on (improve). Sander used a quote to reinforce that we needed to not only work in these skills, but work on them correctly: practice makes permanent. Not perfect, but permanent.
If you take a second to think about it, it makes sense. If you practice a skill incorrectly, your body and brain will remember to do that skill incorrectly. So all that practicing you did didn’t necessarily make you perfect, but you now permanently do it wrong, because that’s what you practiced.
The point is to make sure you’re practicing the right thing. Make sure that you’re doing correctly the skill tour trying to learn. If you’re trying to become faster at typing on your computer, don’t just use your index fingers – use all your fingers. If you’re trying to become a better free throw shooter, make sure your form is correct.
The actions that you repeat (practice) on a regular basis become your habits, whether good or bad. Make sure you’re practicing them correctly first before worrying about anything else.