I know I've asked this before

[james_davis_nicoll]

I was reading a mystery last night that turned out to be a lot shorter than I expected because the manuscript pages were single-sided. The book turned out to be less than 280 pages long. Despite this lack of length the author managed to fit an entire plot between the two covers.

It's comparatively rare for an SF novel to be that short and nearly unheard of for a fantasy novel to be under 300 pages. I've also never seen a mystery that came close to the brick-like dimensions of many F&SF novels. There seems to be a hard limit of about 400 pages over in mystery.

Mysteries also eschew the cliff-hanger ending and the book-fragment approach, which I greatly appreciate.

Does it make sense to ask why modern [1] F&SF readers appear to prefer longer lengths than do mystery readers?

1: I have a number of older books upstairs that come in under 200 pages and like the mystery they all have complete plots.

Comments

[kgbooklog.livejournal.com]

Mysteries don't have any need for worldbuilding and readers don't expect character development (just like early SF) but they do expect the crime to be solved. Still, I can't stop myself from providing counterexamples:

There seems to be a hard limit of about 400 pages over in mystery.

Iain Pears, An Instance of the Fingerpost, 704 pages

Mysteries also eschew the cliff-hanger ending and the book-fragment approach

In Carole Nelson Douglas' Midnight Louie series, the primary love interest makes his first appearance in the final sentence of the fourth book. A later book opens with the main characters making a lengthy list of all the murders from previous books that hadn't been solved yet. I stopped reading when a fairly major cliffhanger was not resolved in the next book.

[martin-wisse.livejournal.com]

That's not a good counterexample as that particular book tried very hard to be the new the Name of the Rose so isn't bound by detective genre limits.