The idea of obsolescence gets a lot of play these days.

We denounce “planned obsolescence” by manufacturers, we complain about our “obsolete” cell phones and other gadgets, and occasionally we laugh at ourselves for continuing to use “obsolete” items from another era.

I am no exception here: I can sometimes be found yelling at my hefty laptop, or listening to shelf-swallowing 8-track tapes on my stereo (yes, I said 8-track tapes—and I also have a record player).

But what is obsolescence? What does it really mean for something to be obsolete?

My dictionary (yes, I own a paper dictionary) offers three related, but subtly different, meanings: 1) no longer used, 2) no longer useful, and 3) out of date, style, or common use.

Interestingly, only one of these three meanings—the second one—is actually a value judgment on whether the item is still useful. Nevertheless, most of us use “obsolete” as a kind of pejorative, as a shorthand for “it may work but it’s too old/slow/clunky and I want a new one.” But this is not really what the word means.

Our everyday definition of “obsolete” both reflects and promotes an ethic of wastefulness by distorting the factor that really defines an item’s value: demand. If an old item (say, 8-track tapes) still has demand in the marketplace, then it doesn’t much matter whether it is “obsolete.” If a five-year-old kid can play Microsoft Pinball on a 15-year old computer, why does it matter if the computer is a decade older than she is? Maybe it’s out of date, but it’s still performing its desired function and can still be used.

To put it another way, obsolescence is in the eye of the beholder.

To the tech-savvy upper-middle-class family, the VHS cassette is long obsolete. But to an immigrant mother with three kids and two jobs, old “video tapes” may be all she can afford. The idea of obsolescence is not objective, and it really only describes, not defines, the value of an item. That upper-middle-class family might toss its VHS collection as “obsolete,” not realizing that “obsolescence” means little to a family that cannot afford the latest (and most expensive) entertainment formats.

The unfortunate result is that many valuable, wanted, and useful items are thrown out because their owners simply do not recognize their value.

Sure, most people still see a market for VHS tapes. But what about the slide rule? The typewriter? The horse and buggy? Those are obsolete, right? Maybe they are—but so what? While these items are no longer in common use, they still occupy small segments of the market, which means that some people still use and want them.

Several websites specialize in selling vintage slide rules; the horse and buggy still works just fine for the Amish; and a surprised typewriter salesman noted last year that college and high school students had become a major source of his sales.

And so we are faced with two choices. We can be surprised that so many people are still using “obsolete” technologies. Or, we can question our own wasteful habit of dwelling on “obsolescence” and relegating useful, in-demand items to the trash heap.

While you decide, I’ll excuse myself and go put on a record.