Whats a gaming failure or undeveloped project you wish had a more successful release/was fully realized? For me its tomb raider angel of darkness. There were a lot of problems with the production, ranging from lack of leadership to scrapped concepts to the unpreparedness of the team for the complexity of programming for the PS2. Core design didnt have enough time to iron out the kinks even with all the crunch time, and eidos didnt give them more time because they wanted to release in june.
The game was an unfinished mess, full of bugs and haphazard level design. But its gained something of a cult status within the raider community, with memes centering on its iconic side characters like janice the parisian sex worker as well as lara's feisty one-liners. Its still being kept alive by a dedicated community of speedrunners and unofficial remasters. I often think what could have been if it had more time to at least be passable at launch. Core planned two sequels that would have continued the story. Obviously they were scrapped, core design went defunct, and tomb raider was handed over to crystal dynamics.
A while ago I picked up an old, sci-fi themed city builder for DOS about settling a new planet with a generation ship after Earth gets hit with a meteor. The manual and strategy guide were hundreds of pages long, every technology, building and game mechanic were painstakingly modelled on real experimental technology. The lead designer was an ex-NASA scientist. It had infinite random planets with different environments based on the statistical probability of elements depending on which star you went to, there were monorails, a politics system, you could create an AI which could go rogue, you could build underground, trade or fight with splinter groups elsewhere on the planet, even launch more colony ships with a space elevator. All this stuff was described in the manual alongside the state of real research into the technologies, how feasible it would actually be to live on other planets, what we'd need. It was absolutely captivating. It was called Outpost. I installed it in a VM.
The game itself looked great for it's age but it was half finished, no monorail, no other factions, no space flight, dozens of buildings in the manual weren't in the game and to top it all off it was apparently mathematically impossible for the simulation not to death spiral. The box also contained a floppy disk with handwritten label and a patch and a printed page of patch notes starting with an apology for the state of the game and a couple of crash fixes.
Ever since then I've wanted to play the actual game they had in mind when they wrote that manual. Surviving Mars has some similarities but the scale is so much smaller.
Also Noctis V. I loved Noctis IV.