P.S. I've been checking back on this topic, because I find it very interesting- and I notice a lot of people focusing on the importance of improving speed. On that point, and as an addendum to my previous post- of course speed is important. Any working artist would agree. You need to be fast.
I remember instances in my progress as an artist where I would struggle to draw a single hand, or spend forever drafting a background because the angle was so difficult for me to grasp (and this kind of thing still happens sometimes). That's not an efficient use of my time. And I would of course encourage anyone who feels they are spending too much time on something because they lack the skill to take some time apart form their project in order to polish that skill. But I think there's a marked difference between that, and rushing a page.
For example- currently it takes me 8-12 hours to complete one page like this from beginning to end. And that's after years of practice. Some people might call that fast. It really depends on who you ask. But could I do it even faster? Probably. Not too long ago, I inked ten complete high-detail pages for a separate project over the course of 72 hours- roughly the equivalent of 3 days- in order to meet a deadline. It was intense. I literally couldn't feel my drawing hand by the final few hours, and spent several days recovering, because I had made myself incapable of holding a pen without my hand shaking. I'd barely eaten and was living on coffee. I fell ill. It was an all round bad scene, and I knew I couldn't afford to do it again.
I know artists who brag about this kind of thing all the time, and honestly I used to be one of them. "Check it out, I gave myself carpal tunnel syndrome- oh, wait- suddenly not so cool now."
Speed is important. But it's not all-important. You don't have to keep getting faster and faster and faster. There's a healthy balance you can reach. Some artists exceed that, because they have literally devoted their lives to improving their speed, and may even do live performances about it. They are the absolute minority.
You are a human- not a machine. Maybe our lives are short, but if you ask me, that just means it's even more important to make them meaningful, rather than making a mad dash for the finish line. So what if you produce fewer projects over the course of your whole life for the sake of a healthy balance? Who is remembered, at the end of the day- the artist who drew hundreds of paintings- or the one who, among however many they did make, created a handful of absolute masterpieces? That's my two cents on the subject.