The long narrative history of older meanings of the two words is also not very helpful. Here's a much better summary (http://www.nobleharbor.com/tea/chado/WhatIsWabi-Sabi.htm) that reads in part:
"So now we have wabi, which is humble and simple, and sabi, which is rusty and weathered. And we've thrown these terms together into a phrase that rolls off the tongue like Ping-Pong. Does that mean, then, that the wabi-sabi house is full of things that are humble, plain, rusty, and weathered? That's the easy answer. The amalgamation of wabi and sabi in practice, however, takes on much more depth."
And I don't think ikebana (floral arrangement) is generally a reflection of wabi-sabi, much less haiku (section entitled "Wabi-sabi in Japanese arts").
Anyway, kind of a mess. Someone should fix that ;-)
 to plug a book on Japanese culture (as it was, rather than as it is now) to anyone with the time or interest, I highly recommend Bernard Rudofsky's 1965 book 'The Kimono Mind'.
I do agree that it gets thrown about as The Essential Guide To The Monolithic Japanese Art Tradition quite frequently on the other side of the Pacific, though. (Those are sarcasm caps.)
When he was a teen-ager, Dorsey told me, he read a book about tea
ceremonies and was impressed by the Japanese precept of wabi-sabi,
which holds that the greatest beauty comes from organization with a
dash of disorder. “The monks rake up leaves, then they sprinkle a few
leaves back,” he explained.
Just noticed that part.
Started as a weekly in 1925, the magazine is now published
47 times annually, with five of these issues covering two-
'Then my favorite fellow Bubba, Jesse Gutierrez, came by to swallow some beers. He told me that he’s been studying Japanese esthetics, and that what I was talking about was "wabi-sabi," the beauty of the humble and the imperfect. Wabi-sabi, declaimed Jesse, his thumbs hooked into the straps of his overalls, was developed to its height by 15th-century tea masters who found that the finish of Chinese Ming porcelain began to cloy. They started buying and exalting absolutely plain Korean peasant ware, stuff that was cracked, distressed, flawed. It reminded them of the beauty of nature, autumn leaves on a stone path.'
It's another way I guess about looking at fashion and what you wear without care (or a little bit of care at least).
Said car is so not wabi-sabi on so many levels it is hard to begin. It has no character, as in the character that an object develops over time. It is not natural or made from materials that are on their way back to nature. Sure it is asymmetrical but all cars are - the exhaust pipe, the petrol cap and the steering wheel.
If you want an automotive analogy, I would look a lot further back, to those cars you find in Cuba, to that Fordson tractor abandoned in a field or a Soviet era truck somewhere in East Europe.