I've been spending a lot of time looking at submission calls, particularly for my anthology listing posts but also in general. I've noticed a few things that turn me off, that make me less eager to send a story to a given market, and thought it'd be fun (interesting, informative -- at least entertaining) to make a list. Stealing a gimmick from one of my favorite review sites...
== If there's nothing in your submission call about what you plan to pay your writers, I'll assume you're not planning to pay us, and respond accordingly. Note that I shouldn't have to click through to some other page to find the pay rate; if you're paying then that info should be in the main call wherever it shows up, and if you're not then that should be in the main call wherever it shows up. If you're doing a for-the-love antho, step up and say so.
== When your list of things you won't accept includes "anything racial" or similar, I have to wonder exactly what you mean by that. If it means you won't take any racist work, why not say "anything racist?" Refusing to take any "racial" stories could easily be interpreted to mean you only want stories about white people -- is that really what you intended?
== Glitches and errors in your submission call make me wonder about your editing skills.
== If your web site is hard to read because of choices you've made (medium to light text on a lighter but not white background, eye-searing colors, text of any color over a full color photo such that random words and letters fade into the background, that sort of thing) I'm going to wonder about what kind of cover you'll choose, and whether I'd want my name on it.
== If your call is buried in your forum (and nowhere else clearly obvious) where topics churn often and there's no permanent link to the vital submission info, I'll wonder whether your records (scheduling, editing, sales, cash flow, etc.) are as chaotically organized as your communication with potential contributors. And about your professionalism in general -- is it really not worth it to you to put up a simple web site with basic info in a stable format?
== Everyone's entitled to their preferences, but if your guidelines page is dominated by an abusive, multi-paragraph rant about (for example [cough]) the stupidity and incompetence of any writer idiotic enough to ever use a semicolon, be aware that I'll back away slowly and never submit anything to you, ever. And I'd probably do the same even if I didn't generally use semicolons, 'cause dude, chill!
Anyone else have any to add...?