"Does this dress make me look fat?"
If the question is asked in the changing room, you can be honest, and thereby prevent your friend from buying something that makes her look like a ship in a tent. If the question is asked moments before stepping onto the stage of an awards banquet, you lie, lie, lie. What could possibly be the value of perfect honesty at such a moment?
People don't consider that principles/values can and do come into conflict: when honesty and kindness come into conflict -- and they often do -- which will you choose? Many would vigorously declare for "Honesty, of course!", as if honesty is the only path to integrity. Too frequently choosing kindness is seen as mere squeamishness, a lack of moral courage. Sometimes it is, of course, but...
Keeping something to yourself, refusing to expose person A to person B, allowing something to pass unremarked... all these various kindnesses can be harder to maintain that honesty. But at what cost honesty? Is honesty always worth the price?
And even then, when hard, clear honesty is the only way to proceed, must it be done without kindness? Must it simply be blurted out because "you need to know", or "you have a right to know", or "you need to get your shit together"? The gut-wrenching pain that honesty can cause needs to be approached with compassion, not blurted out, all the pain only the recipient's problem, because "it's for your own good."
How came knee-jerk, unreasoned honesty to be seen as a sign of integrity or purer virtue? That kind of honesty is the refuge of the simplistic. It's not high-mindedness, it's simply a lack of thought; it displays a certain shallowness of thinking. Why waste time and emotional energy weighing pros and cons when you can simply blurt out the callous facts -- and then claim the moral high ground for your insensitivity?
I can be very straight when need be; I rarely see good reason to be cruel with it. Clarity does not equate brutality, and when pressed, I'd rather err on the side of kindness.
I've often noted that people who dish out that kind of honesty are often outraged when they get a dose of it back... which shows a certain lack of integrity. Someone who weighs the pros and cons of honesty vs kindness, who knows the pain of honesty and deals it only when necessary and only to the degree required, that person will accept honesty when dealt similarly.
Those who dish it out willy-nilly, they don't like getting it back so much.
Methinks they deserve more than they're getting.