The firmest kind of deadline, I think, is a birthday. If you fail to provide a promised physical present - say, a bar of chocolate - by a person's birthday, the assumption is that you forgot or didn't care. Fora non-physical presents this is even more so; bank holidays and empty bank accounts make rather flimsier excuses.
I like writing stories for people - you really can't get a more personal gift - and quite often you can persuade the birthday boy or girl to give you some prompts too, to help inspiration flow. I emailed someone a birthday fic today, which was pretty deadline-tight. I planned it while falling asleep on tuesday night, wrote it yesterday, and proofread it before work this morning.
I can do deadlines. Evidence suggests I need them, if we're honest. Some writers utterly fail at deadlines, which isn't the end of the world (though may result in having to return an advance - about the only time that might happen). I've heard people claim it's an 'artiste' thing - creativity just doesn't work like that - but to be honest, it's just a personal thing. Some people work well to deadlines, some people don't. The problem is when the latter is mistaken for the former; if you can't make deadlines, don't commit to them.
Two things that really helped me were doing an English degree (missed deadlines = failure), and editing the creative writing magazine. After two years of the latter, I was glad not to be the nagging one any more. Our fresher's fayre magazine was a week away from printing one year and consisted, at that point, of two poems. Nagging annoys people, going to print without a regular feature annoys people, putting a magazine out eight weeks late annoys people. Editors have deadlines too, and I've definitely learnt to respect that.
On the other hand, I'm aware that there are a lot of instances where I don't want to do deadlines. It's one reason I'm determined to finish a minimum of the first two books of Greenhelm before I even start submitting it anywhere, and considering my propensity for retcons when later plot demands, I know the sensible thing to do is wait until all three are finished. This may take some time.
For now, I've pledged myself to mini_nanowrimo. I've tried the proper NaNo a couple of times, and I've always had other commitments get in the way (essays with deadlines of their own, for example). Mini NaNo has a much lower wordcount (I've pledged a 100 a day), but the thrust is towards doing it daily, rather than the total words. I could write 3100 words in an evening, and frequently have, but considering I sometimes go for months at a time without putting a word down on paper or screen, I'm quite nervous about the dedication required to write every single day. Luckily, unlike NaNo, I don't have to stick to a single project, so when I get stuck on one project I can at least spit out a random drabble. I've never had writer's block - knock on wood - but I suffer from terrible writer's laziness, where I'd rather sit and read or watch TV and let other people be creative for me. Luckily this is about commitment, not creativity!
Asylum has come back from Electric Spec. I'm expecting a response from Aesthetica tomorrow regarding the competition. Well, they gave the impression they'll respond to everyone, but if I don't get an email I think I know the result! I'm going to retire Asylum for a bit, since genre-wise it's such an odd fish, and it's probably the oldest piece I'm submitting. I now have a big enough 'stable' of short fiction that putting one aside for a while isn't as threatening.
Expect a big change to the website tomorrow too (been waiting for the Aesthetica response). New layout time!