Someone made a copy because there was no (efficient) copy-protection or DRM trying to prevent them from doing it. Specifically in the case of movies and music, it is usually the IP rights holders who preserve it because it is so much easier to archive straight video or audio, than a game which needs a platform (either a real machine or an emulator) in order to work. Straight audio/video is more straightforward to convert to work on future platforms.

It was the crackers and pirates who enabled in the first place that said games could be archived. They made copy-protection free versions of the games that could be preserved more easily, also for future platforms.

Which ones? Archive.org? They let anyone to download the whole MAME game ROM/CHD collection from their site.

It is silly to think that archiving would be performed and maintained by just one individual (person, or group of persons) who maintain it from here to eternity. Let's say there really was e.g. some "historical preservation group" whose sole purpose was to archive and maintain the Commodore 64 game collection. What happens when the members of that group die of old age, or find new hobbies in their life? Does the archive die with them?

How do you even think they got hold of all those archived games, do you seriously believe they had original copies of each and every game, and manually copies them themselves? No, they got (pirated!) copies of said game images from individual people. In that sense it would be also odd for them to keep all that archive only to themselves, when they received it all from outside sources, who happened to have local copies of such games.

As I have said before, I am quite certain even GOG.com has received most of its older games (files) from abandonware sites and such, not from the actual IP rights holders. If there hadn't been any abandonware sites from which to download old PC games but GOG could release only games where they obtain all the game files from the current IP rights holders... the collection of old classic GOG games would be much much smaller than what it is today. So in that sense, yes, you should thank the abandonware sites for preserving the games so that e.g. GOG and others were able to sell them legitimately later.

EDIT: Just so that no one misinterprets what i just said above, I am not claiming GOG is selling illegit copies of games. Naturally they've gotten the permission (or acquired the rights to themselves) from the real IP rights holders to sell the games, no matter where exactly they've gotten the working copy.

Quoting this bit but responding to all of it.

That - or something like it - would be fine by me. The thing is, there should be SOMEthing that legally defines when a game is 'abandoned' and subsequently allowed to be distributed freely, and hopefully within a time period in which the content in question is still relevant. Currently, it's left up to the person doing the hosting and the person doing the downloading, and, well, FREE GAMEZ!! Completely arbitrary, and this leaves any existing rights holders out of the conversation.

I agree that there are problems with content disappearing from public access, but I don't think that humanity necessarily suffers when a 2-star game goes the way of the dodo - that's a side issue, anyway. If copyright law is at the crux of the problem, then folks should work to make changes to the law so that it works for all parties involved. Folks should NOT decide on their own when something has been abandoned and thus free.

For c64 you have the c64pp group and the Amiga has the Software Preservation Society but unlike what's stated their "dumps" is public available.

A piracy debate, yay!
Alright then I throw this question in: Should a cutlass be made of copper or steel?
P-)

On the topic of abandonware "preservation" sites...

Let's ask the million dollar question...
Do you think most of the people downloading are doing so to play the free games?
Or are most of the people doing so, because of games they legally had owned?

I think if most of the downloads are for people pirating games they never owned...that defines the site as what it really is...

I can't say the motives of others (both are probably common motives), but for some reason you forgot one that is just as important as either of those:

Downloading games you never owned yourself (even because it is for a gaming platform you never owned yourself, at least at the time), but you always heard about it or got curious by hearing/reading about it, and don't see it sold anywhere anymore.

Various old arcade games are a good example (MAME; is it really realistic to expect me to find and buy a real working arcade cabinet, if I want to try out e.g. Snap Jack?), as well as old games on volatile media (e.g. Commodore 64 diskettes or Amiga floppies; try buying an original working C-64 floppy today, let alone buying a working C-64 floppy drive and system).

And this gives you a right to play them for free because?

You do know there are companies with permission to sell some of the games from that system, correct?
Some companies have even released emulated copies of their old games...

There are also many working arcade consoles in operation which require you to pay with quarters.

Again, getting it for free without owning it is piracy...
Thus, they are pirate sites...

No, there are no such companies. Otherwise those games wouldn't be 'abandonware'.

Seriously, of course there are...
Have you heard of Amiga Forever?
There are plenty of Atari 2600 game compilations as stand-alone attachments to the TV.
C64 Forever.

Do you know why? Because there really is no such thing as abandonware.

Console arcade systems are still around to plunk your quarters in.

The problem are people like you who think they have some inalienable right to play anything you want for free.

There is still E-Bay or Amazon. Boxed copies of these games and old systems can still be found. It's not as impossible as some make it seem. I have a working C64 and hard drive in my closet. It's really not hard to find working game systems, especially when they were that popular. Don't like the price? So what? Doesn't justify taking them for free.

The whole point of GoG and the DRM-free revolution is supposed to be about all the law-abiding citizens who want a legal copy of old games and are willing to pay for them. But every one of you making excuses why you should be able to download old games for free are justifying the use of DRM. Denuvo is in existence because of people like you. Companies are forcing even the single-player portion of their games to be played online because of you. Companies are focusing on online multi-player only titles because they can prevent people like you from taking the game for free without paying for it. People like you are the ones making everything worse for the rest of us.

There is no point, because, as you said there is no abandonware, that needs to be brought to 'law-abiding' citizens.
So, when are you going to return my money, I've paid for Heroes 4 addons, Frank Herbert's Dune and Blackwell Epiphany? I paid for these games, just like you said 'law-abiding' citizen should and they haven't delivered experience they promised.

And like some people said, GOG is possibly even using the abandonware sites to download the content that they will optimize and sell later with the rights holders' help. Again, a smart rights holder will not go out of their way to destroy sites for games they ceased to sell because of your implied notion of "FREE GAMEZ? Must be piracy!"

Denuvo would have likely been conceived whether LootHunter got abandonware games for free. The point nigh-everyone brings up about DRM is that it is there to protect the short-term window of sales, i.e. the first month or so of release. Someone 'pirating' a game from the 1980s that's no longer sold in any form or shape today is not precisely why DRM was conceived, and I'd even argue that DRM was not a direct result of piracy but rather, the publishers wanting a slice of control over their games.

If Denuvo wasn't conceived to protect against piracy, it could have been conceived against modding, or as a way to permanently shut down the game once its life is over. The ones who made DRM exist, are the ones who are happily throwing their wallets on DRM'd titles.

nope, There is a major difference with playing a game for 1982 and one from 2017. The game from 2017 the company that made it, is still around and selling it, the game from 1982 the company is most of the time not here anymore, and the rights might either be in limbo or somewhere where the publisher can't find it. And a lot just don't care to make these available for sale, and buying of from ebay is just as good as downloading them as the original dev doesn't see a cent.

don't blame people wanting to play games from 15+ years ago for "DRM" today, shoot if I want to play Indy 500 I have to go rummage thru 8 or 10 boxes to find the manual to get past the "keycode" talk about invasive DRM, If I take the amount of time I need to rummage just to bypass keycodes it takes longer just to find the manual than playing the game.

If you want to blame someone for today's DRM Blame the kiddies who download them, also groups like Plaza, Revolt and CPY.

Did you research them properly? Ask your friends?
But I've got news for you, I've paid for many movies which turned out not to be worth my time. So what? Buyer beware. While the companies may have an obligation to make a working game, they do not have an obligation to match your taste.

You've bought 3 games and now because you didn't think they were as good as expected, you have some right to pirate every game under the sun? You are just being silly now.

I'll say it again...there are hundreds if not thousands of games offered for free and I'm not even talking about "Pay to win". Then there are plenty of bundles where you can get games for less than 25 cents a piece. Want higher quality? Many more where games can be had for $1 or less. I find it hard to believe you cannot find something suitable to play that you can acquire legally.

All this talk of people claiming the right to play old games for free or for some nostalgia value because they "heard of the game" is mostly made up crap. It's a justification for piracy and nothing more.

For the handful of people doing it because their old disc is scratched or to find missing language packs, I don't have a problem. But all these people who are saying "Me, me, me" and think they deserve to listen to any music they want, watch any movie, and play any game for free while making every excuse to justify it like "the game isn't really that good anyway"...you are still pirates...

Now I'm curious: What exactly did these games (or their developers) promise that they didn't deliver?

And how exactly I'm to research them without pirating?
Friends? They have their tastes and won't do research or describe their experience in detail (and why should they waste their time indeed?).
Reviewers and youtubers, that can be easily bought? And btw, not all aspects of the game can be judged by video.

Like hell they don't. Especially if they promise to "capture the spirit".

Well, now I see who is to blame for declining quality of the modern cinema. You and other people, who pay for well advertized crap. And who is silly now?

Oh, I can find many games, that I can play legally, especially with regular givaways of old classics and various contests with games as prizes. And I do of cause.

But every once in a while a smartass like you pops up and proclaims about some new title: "This game is a masterpiece! A work of a genius, that no other game will match! And if you haven't played it, you can't critisize it, no matter what!" And of cause until I play the game, all my critisism, no matter how deep or reasonable is dismissed.
So unless I play the game, I can't state that it's a crap. Unless I buy the crappy game, I can't play it. So the only option is to buy a crappy game and thus support developer of that crappy game. Well done!
Heroes 4 was quite unbalanced game. And developers havn't fixed that with two addons (which I also bought btw).

Frank Herbert's Dune was rather clunky as a stealth game. And I mean, you don't make stealth game unless you are able to make protagonist act smoothly. Also no checkpoints on the levels - 30 min and if you died, repeat from the start.

Blackwell Epiphany ending doesn't fit ghost stories spirit (pun not intended) that was the essence of the previous Blackwell games. And plot about commissioner Alex de Silva is completely dropped.