Some games, as many of us know, leave GOG.

It can be interesting to speculate why and perhaps even informative, depending on what others might know.

Now for some games it seem pretty straight forward, and a case of a change of ownership. Supposedly that happened with Duke Nukem 3D, where Gearbox took that franchise over and reputedly don't like GOG, so removed the few Duke games we had.

Not enough profit or sales has been another speculation.
Having to keep up with separate updates for GOG versus Steam etc, is another notion.
Then there is the notion floated that some just don't like doing business with GOG or grow tired of it.
I have also heard that negative game reviews and even attacking the provider, could be responsible.
Maybe some get upset at seeing the GOG version of their game appear on nefarious sites, and don't like to think they are making it easier for the bad guys, with no DRM to be removed.

What else have you heard or speculated as possible?
Do you have greater detail to provide?

In any case, I have always considered it a bad day when a game leaves GOG, for whatever reason. And in some ways it is worse than it never having been here, especially if that means no more games by that provider ever turning up here.

And when I reflect on all the effort to get a game here in the first place, it could be downright depressing.

I don't want to see DRM-free games leave any store that sells them. You've pretty much covered all of the reasons why they might be removed or not show up at all, though.

Main reason is likely the, of course highly subjective "not enough sold copies".
Which, as far as I'm concerned, you can't even bring up as an argument if

- the game was released on GoG well after the initial launch (and patience being a lost virtue in these dark times)
AND/OR
- the game was released on GoG with the most minimal or no advertisement/effort of raising awareness that the game is also available on GoG

A good case study for the second scenario could be the recently released The Pale Beyond whose developer Bellular Studios repeatedly and actively go out of their way to push people picking up the game ONLY on the other platform. Which, of course is entirely in their right, but if you do that then you also forfeit bringing up "we're taking it off of GoG because it didn't sell as much as we had hoped" as an argument, should the game be delisted at some point in the future.

Supraland being one of the more prominent examples where this has transpired in that way (except for the delayed release):

- releasing it on GoG a couple months after the initial launch on the other platform, with more or less zero fanfare that it's now available on GoG as well
- taking it off of GoG again, citing disappointing sales as the reason

Back in the days, when I was able to back projects on kickstarter and other platforms, I asked one developer why his previous game isn't on GOG yet. The game had very high review score and average selling score across all other platforms by that time. He told me that GOG simply rejected his game. That was a big shame, because it was a good tactical turn-based RPG. So i would add a lame GOG curation to the list.

That's a whole other issue, this is about reasons for games being taken off of GoG.

How about changing payment process to another location and then simply not renewing the contract like recettear and chantelise.
That was one of the reasons why the game left gog though i have them both on gog.

As Swedrami said, poor sales that are partially self-inflicted through complete lack of marketing play a part. Take a look at Don't Starve page on Klei's own website - every platform listed including obscure Wii U and PS Vita yet zero mention of GOG. Same story with Mark of The Ninja & Invisible Inc, so that's clearly not just a one-off oversight. Although those three games haven't been removed from GOG, Klei seem to have zero interest in releasing newer games such as Oxygen Not Included and Griftlands here. If the reason for that is 'poor sales' of their existing games that are here, maybe they need to stop and reflect on how much their own 'marketing ghosting' plays a part in that?...

I wouldn't be surprised if many games removed from GOG went through the same thing - launch on GOG after Steam has hoovered up most of the sales, don't even bother marketing what little they do sell here, then remove the games from here whilst putting on their very best 'fake surprised face' at low sales all whilst their own website was actively redirecting people 'elsewhere'...

Dissatisfaction with the store.
GOG not bothering.
Plain old-fashioned rent-seeking behavior in the form of DRM.
Things changing hands and either party concluding to not renew.
Whiny userbase that complains about everything.
Developer/publish not having the foresight to have a basic version that's DRM-free in the first place and having to do double duty supporting different versions across several platforms.
Licensing issues the publisher isn't willing or able to renew.

I'm not saying the aliens did it, but it was the aliens! Or rather the publishers.

That's my way of saying there isn't really a single reason why a game might be pulled off from sale, but a wide spectrum of reasons, and it's always the publisher's choice.

In some cases there doesn't even seem to be a legitimate reason other than the game being abandoned simply because it wasn't "made to last" in the first place. That's an euphemism for "the publisher has milked it and is now moving on".

Or, you know, it's just Epic being a-holes and not caring at all about gaming history. (UT'99 is one of my favorite mutiplayer FPSes, and yes I'm still pissed.)

I don't know any particular reasons (other than what's been stated prior) or specific circumstances, but...

... sure do wish...

... The Long Dark and For the King...

... had stayed here.

One possible reason that hasn't been mentioned yet: The game is suffering from an acute case of remasteritis.

1. Lack of sales
2. Expired licensing
3. Transfer of a game's ownership
4. Remasteritus
5. Developer and publisher had a lovers' quarrel
6. Publisher doesn't think highly of their old games
7. GOG did something that the developer/publisher didn't approve
8. The publisher is resting in peace
9. DRM
10. The game was not legally ready to be released

Pick one.

Fair enough, I did say to speculate. :)
I agree, they can be quite alien at times, even alienate us.

For sure there are multiple reasons.

Another one that comes to mind, which buys into what some others have said, is providing a game to GOG with false intentions, a marketing move, where really they are aiming at getting you to buy elsewhere because of the lame version at GOG or lack of updates. And of course, they often then sell the game twice, so twice as much profit. So in other words, not a true genuine good will release at GOG ... an abuse of GOG and customers really. Then they remove the game when it is no longer achieving their purpose sufficiently or to seem innocent etc.

And then those two games became free at Epic for a week at a later date.

Perhaps some even release on GOG to cause damage by then removing it.

To give the appearance they tried GOG and it failed. A kind of anti-promotion I guess.