Hopefully, this may help motivate some students to learn more effectively. But a disquieting counterargument has arisen in some quarters. Is a new edition really needed? Perhaps an earlier edition would suffice for most students. If so, this would let several buy second hand versions far more cheaply. But if the publisher goes to this edition, and it is made mandatory by a school, then it is far harder for students to find used versions. At least for a few years. And later? When those used editions start circulating, what if the publisher and school then go to a newer edition?