Why bother practicing anything?
Also, for the sake of argument, let's say it doesn't really matter what you practice. You could be practicing law, tennis, meditation, a musical instrument, sobriety, writing... usually, when I talk about practice, I'm talking about drawing and watercolor. And I'll get to that shortly.
Whatever you practice, you're usually going after a result. Generally, you want to "get better" at or master an activity or experience. Maybe you're in it for the competition, with yourself or someone else. For a score or an accolade or, simply, just to do it.
If you measure practice on a graph, you are not going to see a straight line ascending at an angle. That graph line will shoot up one day and plummet the next. Or plateau for long periods of time. Again, that's generally speaking. If you're Federer, with a lifetime of discipline, your calendar planned at least a year out, surrounded by a support team and trainers, your results might look different but even someone at the top of whatever game they're playing has to manage daily practice and deal with daily results.
If you're not a pro and don't expect to master whatever you practice, why bother practicing anything? Every discipline has its own set of rules and regs and quantifications, but just consider your personal experience and level of satisfaction with a practice.
No matter how long you've been practicing, you're not always going to be happy with your results. Which means that you're not always going to be happy with yourself. You're going to succeed sometimes and you're going to fail. A lot. You're going to trip and fall and hurt yourself. Even if it's just with the thoughts you think about yourself (which can be more damaging than a broken bone). Like it or not, that's just the way it is.
But the true value of practice is that every time you set out or sit down to do so, you meet yourself. You show up to practice, you meet yourself in whatever condition you find yourself, and that, right there, adds up to a lot.
"Exercittio potest omnia." *
(Practice makes all possible or Practice is everything!)
*Often (almost always) mistranslated as "Practice makes perfect."
Contrary to popular belief, it is your weaknesses, your limitations, that give you your personal style. No one else in the world has your particular set of strengths and weaknesses. If you can learn to embrace your weaknesses, you can turn them into strengths.
Above, the simple, charming, kind of wonky, drawing of a chair was made by Van Gogh during the last four months of his life, after many, many years of practice. It might not hold you up if you tried to sit down on it, but it certainly is alive. And unmistakably Van Gogh.
What do you practice that makes you feel alive? What have you learned through that practice that makes you unmistakably you?