Obviously, I’ve been reading a lot of author and editor interviews and stuff about writing workshops. For a group of people who really ought to follow Orwell’s first maxim, it’s surprising how many of them declare in exactly the same words that the chief value of short fiction is to “hone your craft.”
The quote that got bastardized into that meme is actually Larry Niven’s: “Keep writing short stories. The money’s in novels, but writing short stories keeps your writing lean and pointed.” The difference in implication is substantial.