Er, "lucked out"?

I believe it was George Bernard Shaw who said England and America are two countries "separated by a common language". And how! As Liane detailed in a previous Novel Spaces post, it's not just a question of "o" versus "ou" or "ward" versus "wards". The differences in the usage of the language itself go much deeper than trivial spelling changes, which is why I'm always relieved and ecstatic to hear that a US-based publisher is not averse to accepting my UK English manuscript and, what's more, is happy to publish it in UK English. (So rare, so precious!)



Most of the time I just take note of the dissonance between the UK English and US English terms and move on, but I have to admit being stumped by a recently popular term.



Lucked out.



I believe this is supposed to be a good thing. I've been told, for example, that I "lucked out" on my book covers. I had to ask, but it appears to mean that I've had a lot of luck with my book covers. (And it's true, I have.) My question is, though, how can you reach that conclusion from that term?



Take similar phrases. "He bled out on the sidewalk." Good? I don't think so. "She flaked out in the exam." Good? Nah-uh. So how come "lucked out" is seen as something positive?



Okay, "luck" is nice. "Lucked"? I think you're starting to hit slippery ground here. Think of other words that end in "ed" (and perhaps even rhyme with "luck"). Like, sucked. (What's the matter, were you thinking of something else?) No matter which way you cut it, "sucked" isn't such a hip and groovy word. (I'll just pause for an undergraduate joke -- Gravity is a myth! The Earth sucks! -- and move on.)



Now add "out". Where is "out" a positive term? Who can show me that? You strike out. You're "on the outside". You're "out of the loop". You're "out there", "out of your mind", "out of options". Okay, maybe "break out" (the "break-out novel"! I wish!)? "Pay out"? Though, in both situations, it depends on which side of the fence you are on as to whether it's a positive or not.



Can you tell I've spent many neural cycles on this one? Lucked out? Even as a series of sounds, it doesn't sound very...appetising. "You really lucked out!" Try it out aloud now. See what I mean?



I'm sorry, I just can't see it. Why is this the current favourite over a much more serviceable, imo, "got lucky"? "You sure got lucky with your covers, Kaz!" Anybody care to explain?