Navagon: Yeah, that's really just not true at all. It would still be interesting if that's what GOG actually told them though. I doubt it's a quality issue though as the game is a hell of a lot better than some of the ones on here.
I suspect there's some truth to what RadonGOG was told. It's likely to be a case-by-case scenario where GOG evaluates the market viability of games and accepts or rejects them on that basis. So age is probably a factor, but not the only one.
It's simple economics - newer games are still viable in terms of their sales potential, but there are likely to be a number of other factors that GOG takes into account:
* How high a profile does the game have? Has it been heavily marketed/publicised in mainstream media?
* Does it have a focus on online multiplayer? Is that online mode dead in the water? Is it likely to be? (online focus is usually a certain sales killer)
* Has it been released DRM-free before? (i.e. Was it a Steam/UPlay/Origin exclusive?)
* Has it already been released in PWYW indie bundles?
Older games are probably only likely to be accepted if they are higher profile, like Torchlight for instance. Obscure games that have been languishing on Desura or Steam for a year or two and have done the indie bundle rounds already are not likely to be big sellers.
In the case of QUBE, it's been on Steam and Desura for some time. I also could have sworn that it was in an indie bundle, but guess I was wrong as I can't find it. I think it's safe to say though that its peak has passed.