Be careful with this one. It's very much possible to state a reason and still express that you won't change your mind on the matter. Although it is more effort, you won't lose people's goodwill.
If you're a family member, friend, coworker, etc.--i.e., someone who has a reasonable expectation of my putting aside whatever I'm doing to consider your request--then this response would be reasonable. (But even then you have to respect the other person's time.)
But that isn't what the author of the article was describing. He was describing people who had no valid reason to expect him to be at their beck and call, still treating him as if he were at their beck and call. Such people are not entitled to a reason, because they're not entitled to any claim on your time in the first place. A polite "no" is enough.
(I should probably also clarify that by "friend" I don't mean "someone I just met on Facebook" or "someone I have a few beers with once in a while". I mean someone you have known for a fair amount of time and with whom you have mutual trust.)
The remark in parenthesis is pretty important here. A lot of people seem to feel entitled to your full and immediate attention 24/7 just because they're family or know you for a while. I suppose GP feels that too ("what, you think you're so important that you can brush me off just like that, and I'm not even worthy being given a reason?"). There's this strange phenomenon when people in some sort of relationship start treating the other party with less respect they'd show to a stranger.
I spent a lot of my late-teen / young-adult years teaching people around me that yes, I'm always open to help, but if you want me to consider your request, please respect my time and focus - it'll be better for both of us. I even translated PG's "Maker's Schedule, Manager's Schedule" just so I could show it to my mom (and some other) in order to explain why I don't respond well to being asked to do trivial errands at random times during the day.
At work I simplify this - when I want to signal I'm concentrating, I just put on over-the-ear headphones.
And mind you - I'm probably one of the more accommodating person you'd met. I find it very hard to say "no" when people ask me for help nicely. What I wrote above is the result of dealing with years of frustration and eventually deciding it's too much.
I had not even thought of doing this, it's brilliant. I often run into this issue with my mother when I visit, even though I am her adult son. I will certainly try this.
Anyway, for people from Poland who might find the essay useful, here's the translation: http://esejepg.pl/eseje/makersschedule.html. There are also some others (in particular, I wanted to have "What You'll Wish You'd Known" available too, to show to my younger siblings).
(I'd also love to get some help with translating more of the essays. After some personal issues back some 4 years ago I lost the drive to continue the work; since then, however, I've been told those translations are actually being printed out and given to people in some business classes, which sounds like they're useful to someone.)
It's not rudeness, but honesty that makes me dislike giving reasons. Sometimes I give the reason "I don't want to" which seems about as correct as I can understand.
edit: I have found this especially true in family/personal matters
If somebody thinks you lazy, so be it. But you don't owe anyone a reason.
Reasons, as you see them, are often "excuses" to the other person. Mught be even worse. Now you're not just lazy, you also make excuses.
Personally I'm bad at this too. I often give reasons/excuses when there's no need and even more often I say No by not saying anything at all and waiting for the thing to pass.
If saying the reason would not lead to people taking advantage of it, I would say it. But with many people it does.
But I would not just brush you off, actually. I would attempt to find a way to help you if I would see one or attempted to redirect you to someone who can help. So even if I wont do what you want, unless I have bad experience with you personally, I would try to figure out alternative solution.
It depends on who you are in the scheme of things. If you're a friend, colleague or family member you have the expectation that you can depend on a person because of your proximity to them in a social network. No usually does need to be qualified in those cases. But if you're not closely tied to a person in a network and request something from them, to expect a reason or explanation for non-compliance is unreasonable.
Social networks often act as ledgers for who owes whom what and when you're asked by someone who is a distant node in the network to do something the risk is greater that your actions won't be reciprocated in some form, even if its simply an acknowledgement of what you did for them, because you can't appraise their character.
Caveats: Money is a shortcut through all of this social-ledger malarkey. My explanation ignores time as a cost factor. I can't back any of this up with facts.
> "System 1" is fast, instinctive and emotional; "System 2" is slower, more deliberative, and more logical.
When I'm imposing on your time it's only normal that you get a chance to say 'no', whatever the reason for it.
There's nevertheless a psychological difference between (variations on) "sorry dude, too many things on my plate this week" and "No.". There's nothing about the former anyone one can argue with, but it shows that you value basic human mutual understanding.
If the couch-owner truly lacks self-awareness, to the point where they constantly badger you with unreasonable requests (we all know that one guy), then a "No." isn't going to enlighten them either – in that case, you do them a favour by respectfully but explicitly informing them that their request is unreasonable.
I have a friend like this and, while we get along great most of the time, he is always interrogating people who say no to him and you can just tell he's assuming 'the true reason is laziness'.
People make complex decisions and they shouldn't always have to explain why. Especially with someone you trust.
I.e. if in the way you ask you show you're expecting them to comply, you're doing it wrong. Show respect to people's need for autonomy, and they'll be more willing to help you out.
"No, I can't do that for you at 5pm on a Friday. I can have it for you by noon on Monday, you can ask X to do the work, or you can invent a time machine and go back 24-hours and give the work to me yesterday."
I have incorrectly assumed that time or money were the priorities, but with a little more information found out something else was really driving the request.
What about the laziness of not handling the matter yourself? Talk about entitlement!