I'm certainly not one of those. The first novel I ever wrote will never see the light of day. (The January Machine, a science fiction thriller written in 1994 about time travel, zombies, the Rapture, the next ice age, and reverse serial murder.) On the other hand, kenscholes sold the first novel he ever wrote, Lamentation, to casacorona at Tor Books, via arcaedia.
In my case, I tackled three novels early on, well before I got good enough to sell short stories. Number two eventually found a home in the independent press after a blank-sheet rewrite, Rocket Science [ Powell's | Amazon ] to Fairwood Press. You'll see number three one of these days as well, Death of a Starship. (Also a blank-sheet rewrite, around number seven or so if I count that separately.) I rather like number four, The Murasaki Doctrine, but pretty much no one in the publishing industry does. Mainspring [ Powell's | Amazon | Audible ] was the fifth novel I wrote, sixth if you count the ground up rewrite of Rocket Science as a separate effort. I have a completed YA manuscript, Other Me, which I need to revise and send to my agent, and I've sold everything else I've written since Mainspring.
The key for me was I started writing (or rewriting) publishable novels after I started writing publishable short fiction. So did kenscholes, he just didn't bother to try until he had his short fiction chops wired pretty good.
This does not suggest that writers should enter the field through short fiction. It does suggest that writers with some facility for short fiction enter the field that way. If you're one of nature's novelists, write novels. Don't kill yourself in the short form if the short form feels like you're killing yourself.
On the other hand, if you like the short form, I highly recommend it as a career path.
Have you sold at least one novel professionally?
Did you sell short fiction professionally before you sold a novel?
Was the first novel you sold the first novel you wrote?
If it was not your first sale, did you eventually sell your first novel?
If it was not your first sale, are you marketing your first novel now?