I understood the question. Watterson's brushwork is so economical and confident, I could see how it might look sloppy and slapdash to a "civilian." What was evident to me--but, as I was reminded, not to everyone--was the bedrock foundation of artistic fundamentals underlying it. Perspective, composition, expression, use of negative space. Watterson was also particularly smart about what he didn't draw. For example, if you or I set out to draw two characters walking through a snowy field, we might show drifts piled against fence posts, icicles hanging from tree limbs, rocks protruding through a crunchy crust. In contrast, Watterson followed Walt Kelly's directive: the best way to draw snow is to draw nothing at all. Feet disappearing into the ground, a scraggly weed, everything else blinding white as far as the eye can see. With such scant clues, you still immediately get a feel for how deep the snow is, maybe even its texture. That's fine cartooning.
I'm reminded of Jack Benny's ability to get laughs with silence, the audience reading his mind and filling in funnier responses than he could possibly voice. One imagines that the perfect cartoonist would somehow be able to communicate an idea by drawing nothing at all.
(Remember my post on Victorian era cartoonist Phil May? "When I can leave out half the lines I now use, I shall want six times the money." A cartoonist who figures out how to omit all the lines should get all the money.)
Of course there's more to cartooning than economy. A fairly common topic among cartoonists is "artists I didn't think were any good when I was young but love now." You hear names like Steve Ditko, Alex Toth, Chester Gould. My example is a comic book artist named Don Heck. When I was a kid reading Marvel Comics' "Avengers," Heck's credit on the title page made me groan. Part of the problem was that in the 1970s, when I was a young teenager collecting comics, Heck was in poor health and winding down his career. In addition, he was often called in to do rush jobs on tight deadlines when other artists couldn't. Frankly, I didn't catch him at his best.
But my main problem with Heck was that I just didn't "get" his style, which was so different from either the pop-art Jack Kirby or super-slick Neal Adams styles popular at the time. At his best, Heck did loose, sophisticated, impressionistic, dynamic brushwork in the tradition of newspaper great Milt Caniff ("Terry and the Pirates," "Steve Canyon"). He had a great eye for layout and storytelling, and a successful career in romance and western comics before superheroes hit big in the 1960s. It wasn't until I learned a little about the history and craft of cartooning, and maybe tried to do some myself, that I really appreciated how tremendously skillful he was.
Art by Don Heck ca. 1966
I've learned you can come to respect work that you don't particularly like. I recently had a cup of coffee with a syndicated cartoonist, during which the conversation turned to a comic strip done by another syndicated cartoonist. "I don't really like his strip," he said. "It's just not my thing. But you can tell at first glance that he's a great cartoonist who belongs on the comics page." I think that's a mature way to look at things, and I've got a fairly long list of artists like that: I'll probably never buy their work, it just doesn't appeal to me, but they're obviously very skilled professionals doing terrific stuff that somebody out there will really appreciate. I'll also admit there are artists I still don't get despite the raves of people whose opinions I trust. I'm always open to the possibilities that either they're wrong or I need to get educated.
How can you tell the good from the bad? The "so good it looks simple" from the "looks simple because it really is simple"? I'm not sure. Read a lot, I guess. Good cartooning is always clear; if you have to stop and go back because you missed something or don't understand what a character is doing or how the action progresses, that's a failure (the cartoonist's, not yours). You shouldn't have to think about it. If a piece of writing or art makes me care about the characters and feel something--happy, sad, even appalled--I figure it's doing something right.
Honestly, I think I divide other people's work into three categories: 1.) I could do that. 2.) I wish I could do that. 3.) Wow, I have no idea how they did that. I think many people's taste evolves and matures as they realize that a lot of work they thought fell into Category 1 really belongs in Categories 2 or 3..