I used to have a rule of thumb:
A novel would get 50 pages before I dumped it. That was, I'd give it 50 pages and if it wasn't interesting enough to me, I'd dump it. A short story I'd give a couple pages, depending on the magazine, book.
Now I give novels 1 page to hook me and a short story 1 paragraph, two at most. I just don't have the time to waste on dull stories any longer (unless it's Don Quixote

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