Actually, you’ll find multiple priceless quotations within the article I’m about to cite. Here’s just one, within the rubric of “guidelines for authors”:
1. Never, ever read longer than 20 minutes. Fifteen is better. Ten minutes if there are more than two authors on the docket. Practice reading in the privacy of your home using your microwave oven timer. Note that 20 pages do not equal 20 minutes; 20 pages, especially the too-beautiful kind, go on forever.
Source: “Elinor Lipman Provides a Guide to Author Anxieties” (thanks to ThereseWalsh for the find).