Those aren’t the only differences. I never finished that first one so many years ago, I gave up on it. I put some colors down, and made a science-fictional space scene, but the colors weren’t right, and I didn’t know how to mix color back then, or about underpainting, or anything really, and that was the end of that painting.
Since then, I’ve learned about color theory, underpainting, scumbling, and how to start, and (more important) how to finish a painting/piece of art, and not to give up until it’s done, or until I know it’s unsalvageably bad, at which point, I’ll start over.
I will go on and finish this painting, it may change in many ways before I’m done, but it will be done. Then I’ll go on to the next one, and then the next, and so on. And that is what it is, and what it takes, to be an artist, whether you sell your work or not, is to keep going on to the next one. It’s not about the one you’ve finished, but about the one still inside, the one yet to come.