As j4 put it more eloquently last month, everyone knows that the use of the word "friend" in the context of "friends list" is, well, sometimes overstating the case. Certainly some Friends are friends and certainly some friends are Friends, but both are "some" and not "all". I'm sure there are some people who are very friendly with everyone whose journal they follow using the Friends feature, particularly those who keep a tight rein on their Friends list. However, I suspect this is fairly rare.
I'm sure that people feel from time to time that they want to say "Hi, I added you to my Friends list, but your journal turned out not to be what I was expecting. You interest me no longer; accordingly, I've decided that I don't want to continue to follow your journal." to someone when they take them off their Friends list. I'm sure that it must have happened, but I cannot remember ever having seen it happen. The Great LiveJournal Lie is that people never, or vanishingly rarely ever, say that when I'm sure that they must think it from time to time.
Of course, this isn't entirely a bad thing. Tact is much to be admired and LiveJournal as a whole gains from tending to avoid major recriminations, defriending wars and the like. Certainly there are high-profile fallings-out from time to time, alongside many more low-profile ones, but I'm pleasantly surprised that there aren't more. This goes back to a long-held suspicion of mine that, for most people, keeping a LiveJournal is at least partly performance art and that public fallings-out are poor performance. On the other hand, part of the old advice is to find good enemies. Perhaps it's just that defriending-wars don't make for interesting debate.
Without wanting to point fingers at any people in particular, I guess that perhaps 10% of my friends list have trimmed their lists saying "Sorry, I just don't have time to follow as many LiveJournals as I used to". I'm not accusing them of lying. However, I think it is important to recognise that people's tastes change over time and that there's nothing wrong with finding you're less interested in a particular topic than you used to be, which goes alongside being less interested in sharing it with the same sort of people that you used to. There is an unspoken "I'm not as interested in you as I once thought I was" to the people who get deFriended in the cut.
It's implicit that when someone removes you from their Friends list, they are to some slight extent expressing disinterest in knowing you. This is where the terminology "Friends" is particularly unhelpful; by removing someone from your Friends list, there is at least some slight throwback to "I don't want to be your friend any more" from your youth - or, even, romantic breakups. It's also true that not being interested in someone is a particularly personal sort of slight to cast. People define themselves (subconsciously even if not deliberately) by the way they spend their time, not least by choosing to define themselves as someone who continues to maintain a LiveJournal. To declare that you aren't interested in someone at least partly because of the way they have chosen to define themselves... well, it's very honest, but I can't see how it can get much more personal than that.
On top of that, there are all the funky things that you can do with Friends lists, such as the famous Joule tool so that people can track the changes in their Friends-of list from day to day. Of course, you can check Joule for other people as well - and so get an impression of how seriously they take LiveJournal and their Friends-of list by how frequently they check it themselves. Perhaps this is taking LiveJournal too seriously. Perhaps I'm just bitter because watchful_entity defriended me twice! :-P ;-)
There has been discussion from time to time that functionality will be added to LiveJournal to distinguish people whose journal you follow from people to whom you reveal your Friends-only postings. This doesn't seem to be a particularly sizeable improvement to me; it would still be a strange sort of half-slight to trust someone with information but declaring publically that you don't find them interesting enough to read, or that you read their journal but you don't want to trust them with your (relative) secrets. In any case, this is just a specialised application of LiveJournal's already-existent and very powerful filtering technology.
LiveJournal's filters are definitely a double-edged sword. Having the ability to restrict who sees your postings is tremendously useful. On the other hand, their existence raises the theoretical possibility that you aren't seeing everything that any of your Friends post and you can never be sure of this. Admittedly private posts muddy the waters a little; for instance, go to this post of mine and click the right-arrow button (the rightmost one in the blue box at the top). You won't be able to see the next post - you'll get a "no permission" error. Now I claim that this is because the next post is a private one I made to myself to remind me of a later posting to make while on holiday; however, you have no way of knowing whether this is true or not. It could be a post about you and your most intimate secrets which I have made to everyone on my Friends list apart from you in particular. Of course, I claim it isn't; of course, you don't know whether this is true or not.
One related question is "Would LiveJournal be as interesting and useful without more-graduated-than-Friends-Only filters?" I would imagine that, without filters, people would habitually start up multiple LiveJournals and just change the Friends lists to produce the same sorts of results as before. This strikes me as needless duplication of resources and so not an improvement on the current situation. It's also true that some people maintain more than one journal already in exactly this fashion. I can't prove I don't and certainly confess that I've thought about it as a concept in the past. I place no value judgement on it as a technique; if it works for you, go ahead and use it and more power to you.
So you can never be sure that you're getting the whole story from any of your Friends. In fact, you can't even be sure that those of whom you are listed as "Friend Of" really are reading you; it's quite possible that you could have someone listed as a Friend, but only view some restricted subsection of your Friends list, never looking at anything they have to say. In fact, it's only people replying to your comment (or noting it in some other context) that offers some sort of proof that they are paying attention to you at all. You don't know whether or not I read your LiveJournal even if I list you as a Friend. This is a frequent technique that people use when they don't want to follow a journal any more but don't want to risk offending someone by deFriending them. Yes, this is one relatively frequent manifestation of The Great LiveJournal Lie.
I lie in exactly this way too. However, I am honest enough to admit in my userinfo that I don't read all my Friends' journals all the time. Yes, this is in part because I turn out not to have so much in common with some people as I thought and have been enjoying other people's journals less than I had expected; you will have to take it on trust that I do read all my Friends' journals from time to time. (It's also in part because some of you post so damn much, to add another voice to the "many short postings" or "few longer postings" / to lj-cut or not to lj-cut debate.)
This all sounds terribly grave and mistrustful, but all things considered, I welcome and relish the power and flexibility that LiveJournal offers and just feel that we need to bear its downsides in mind as a consequence. People's tastes change over time and that's a good thing. People do go through "more interesting" and "less interesting" phases and that's only natural; I feel that I've been on an extended "less interesting" phase since... well, at least since my return from the MSO, arguably a lot longer. (ringbark once said he liked my journal because it contains details of what I've been thinking of, rather than what I've been doing. I really feel that I haven't had any particularly interesting or imaginitive thoughts even by my own standards for some time now.)
If you'd like to hoist me by my own petard and say "I really haven't been finding you very interesting really" or "I only Friended you because we met and, you know, you're not what I expected in your LiveJournal based on how you are in real life" then now is an excellent time to do so; no hard feelings and we'll shake hands next time we meet. I'd like to LiveJournal in a world where the reverse would be true, too; this post is my way of doing my bit towards this goal.
Yet I don't have the courage of my own convictions; I'm just as big a LiveJournal liar as the rest of the world, preferring to filter unwanted Friends out rather than deFriending them altogether. Even though I really have trimmed my Friends list, the only three journals caught in the cull had all been deleted anyhow. :-)
Finally - and with no relation to the above - many happy returns of the day to petulans!