This is one big reason i have extra, i have many discontinued products that cannot be replaced.
By having extra i am set for a decade or two in many cases.
I of course am guilty of this …. But going thru some stuff I saw … an extra Utorch C4 charger . Not a v4 or an Lii-500 that I might have spares of . The C4 has been a daily driver for years and years now , having replaced so many other chargers .
I’m pretty sure it was bought with the idea of reselling or gifting but due to my fondness of the one I’m currently using it’s going to be squirreled away as a back up . Sometimes two or more is the exact correct number .
Thanks go out to Toddshoe who heard my tears and fears about gifting my spare Jetbeam jet-1-mk AA and sent me a second one just to soothe my increased anxiety over only having one . :p
my father was guilty of this and had two grand torinos, two cutlass supremes, two caprice classics and two park avenues…. It’s in the genes and if pushed I’ll just blame my parents for my insanities .
The Devil made me do it !
Now go buy two Ts-10’s Wurkos needs your money !
My beater light was out of commission yesterday (being charged) and i was stuck without the light i needed.
Perhaps i need an extra 
I got too many just-one-of lights that I don’t use and really should pare down, but lights I like and really don’t want to do without, yeah, I’ll get doubles or more.
Gets busted, gets lost, gets swiped, naw, I don’t want to be without.
Sometimes I’ll get multiples of the same thing with the intent to gift ’em or something, ’til I start getting weird looks at even suggesting gifting a light.
Duplicates of stuff you like is a good thing. I look at it the same as buying insurance - you hope you don't need to use it but if you do then you are prepared. When you start getting duplicates of duplicates then you might have enough of that item.
It seems the most likely thing to break is the one you don't have a backup for.
It seems i have double of things that i suspect will stop being made. Or will jump in price (i have bought multiples of items on clearance especially when they are generic and i will use them up).
With a few exceptions, the tablets are the new one and the old one which is relegated to simple tasks since it lacks memory or processor power to do the most modern stuff.
I must have around 20 Sofirn C01 from both batches.
The best Sofirn ever made.
Many of my lights, I think I’m around 105 now, are multiples. But, I would usually try getting a different led in the other ones. Sometimes I’d get the warm tint for general use but also the cool tint led to see max output. I know some people that would buy two samples, test them, and only keep the better binned example.
Another thing that I would think about is the average cost of the lights that I purchase or even the amount spent over the years. Overall I’m really thankful to have what I do.
2=1
1=NON
One more reason came up, the ability to swap out a dead device without having to make time and energy to go to the store to get another one. And stuff dies at the worst possible time when your super busy.
My condensate pump broke a couple years back i was able to swap in the one from the dehumidifier without having to forego heat or pay a tech to come over and sell me an overpriced one on the spot plus labour charges.
I’ve things I’d replace like for like if they got lost/broke, but I don’t have space/funds to hoard duplicates of everything.
I’ve had backups of a couple of things in the past, but then technology/designs move on and new and improved versions appear.
Perhaps an extra sofirn C01S would have been good when they were on offer, but I have other AAA lights that would be fine, so I think I’m just being greedy… 
You should be smart what you buy extras of, i don’t buy two cars or two fridges or two desktop towers and so forth.
But i do buy two bottles of pop or two 21700 lithium ion batteries for example.
I get what you’re saying, but I have enough ‘stuff’ already, firstly, I don’t have some sprawling mansion to keep it all in, secondly, I do not subscribe to the consumerist philosophy of consuming more and more ‘stuff’.
To give examples of technology moving forward, I bought a few extras of 30Q 18650s, and now 21700 seems more popular for medium-large lights…if I didn’t have 4x extra 18650s I’d probably have started getting 21700 lights and cells, but it seems superfluous when I have 4 cells
Or, my favourite headlamp at the time (Zebralight H51c) is now two generations old, it’s still a good light but I’m glad I have the $65ish rather than a second H51c… I hope that makes sense.
As per thread title- “Has to have duplicates…” Implies must, sure I get that sometimes extras of things are nice, but for me, it’s not critical.
I wish i could say i had a mansion but alas no such luck.
And newer technology coming along is a risk but on the flip side are items that get discontinued and cannot be replaced.
There are items i wish i had bought because they are no longer made.
Hell i wish i bought Tesla stock a few years before covid, i would have made a killing and could buy that mansion.
And selling it before Elon bought Twitter.
Yeah, I don’t even have the Mc kind.
That’s the biggest issue. And “improved” models often aren’t.
As nice as the original SC31 (?) was, the v2 and pro and other versions just became more “me too!” lights, whereas the original was perfect for The Muggle. And no one in Hell’s Creation has any of them anymore.
The WK30 was nigh perfect to me, even with the 395nm and regular red. 365nm wasn’t a plus with visible blue-white spillage, and deep red doesn’t do much for me. And I think other things changed, too.
MH20, awesome! MH25? Had some things that bugged me.
A lot of LITOM lights on Amazon, I wanted to get more of as gifts… discontinued.
Bayga weather station for 11bux via vipon. 30 now. Wouldda been worth it to stock up just for the remotes, as the base can take up to 4. (I got that only on a whim, to make sure my freezer wasn’t sneaking up above the freezing point, so it could read remotely and store max/min temps on a 24hr cycle.)
Man, so many things I was debating to get more of, and missed the opportunity.
I wish i had bought some more 4AA lights since they are incredibly rare now.
I have often immediately bought duplicates of things I liked, or things I thought were an especially good deal or likely to be discontinued. Flashlights, pocket-knives, watches, things of this nature. One to use, one to “put away”. Even shoes.
I guess maybe it comes from the experience of owning something for many years, then finally it breaks or gets lost and I cannot find a suitable replacement. Damn, I wish I had another one of those.
Yeh, I got a Secret Stash (somewhere… fiik where I stashed ’em) of TK4As when the getting was cheap.
Still got a Cave Man, which takes 8 nominally but they’re 2 parallel banks of 4.
Yeah, never know when shtf and you might need ’em.
Yeh, was at Modells just for s&g with a cow-orker, and saw some running shoes being blown out at I think 20bux/pair, so got 2 pair.
Wore the first ’til they practically fell apart and wore through, and were still comfy. Still working on the second pair.
Same with water-shoes at Kohls, was intending to use ’em as “slippers” in/out of the house, and again being discontinued at 17bux/pair, got like 3 pair. Damned things last forever, still on my first pair, no sign of being worn down, ripping, nothing. (Similar ones are 40-50 now.)
Little Choinese store near where I worked, got 2pr of rubber flipflops. Again, first lasted forever, working on the second pair. Years ago, never found anything comparable since.
So in some cases… score!
Times when I’d forego getting dupes, I end up regretting it.
I usually have the same dilemma! Should I buy multiple of the same thing if I really like it, or should I use the thing I really like well, then look forward to a potentially new product in the future? I guess the problem is sometimes, new isn’t always better!