Let’s paint a picture for you. Mass Effect comes out on systems and PC’s and the world is taken away on a grand adventure. Then, in the sequel, the story and characters carries the day to the ultimate victory (if you did the loyalty missions that is.) Then, the third and “final” game came out, and for 95% of the game, you’re loving every minute of it. Then, the ending happens and everything just feels…ruined.
If you don’t recall, the game’s ending would have you either wiping out the Reapers or changing their programming to become better, or even have a “synthesis” with them that creates something new. But in the OG ending, the mass relays that you used to get across the galaxy were all destroyed, basically stranding everyone in the Earth solar system, and making all the hard choices you did…kind of pointless.
It should be noted that game’s original writer, Drew Karpyshyn, didn’t work on that ending, nor the entirety of Mass Effect 3. Yet he did reveal on Reddit that the ending for ME3 was planned in part well before things got into development:
“As for Mass Effect, we had some very rough ideas planned out,” said Karpyshyn over on Reddit. “Basically, it involved luring the Reapers through the Mass Relays then detonating the entire network to wipe them out… but also destroying/damaging the relays and isolating every galactic community from the others. But we still had to figure out a lot of the details, and there were some issues with that option… like what we would do in the next series of games.”
So yeah, originally, things would’ve setup more games, which fans would’ve loved. Instead, the ending sucked so bad for gamers that Bioware had to augment the game for better endings where the mass drivers were just damaged, not destroyed, and some new choices like “Refusal” were introduced.
Source Reddit