A bug on Overwatch's Control maps wass affecting skill rating adjustments, but Blizzard has found and squashed it.
Earlier this week, Overwatch Principal Designer Scott Mercer talked on the forums about a possible bug that could be affecting Control maps in the game. Users were reporting that stats on those maps would stop recording after the first round, leaving them short on XP, and making those matches have very little effect on player rankings.
Mercer said at the time, "There are legitimate reasons for the magnitude of skill rating change to vary on a match per match basis, but we did get the feedback so we're investigating to see if there's a consistent bias or simply an error on Control maps (Ilios, Nepal, Lijiang Tower). If we can identify it, we'll then work to address it quickly."
The bug turned out to be real, as Game Director Jeff Kaplan confirmed yesterday. In a post to the forum, he wrote, "Last night, though, we uncovered a bug that is causing skill rating to not be adjusted properly in our Control Maps (Nepal, Lijiang Tower, Ilios). This bug is a top priority right now and we're hoping to have a fix ASAP." Further down in the same thread, he also said that the company has "No plans to reset skill rating," in the wake of this bug being discovered.
Last night, Overwatch Community Manager Lylirra reported that the bug had been squashed. "Last week, several players reported that wins and losses on Control maps (Ilios, Lijiang Tower, and Nepal) during Competitive Play were not correctly influencing Skill Ratings. The exact problem causing this to happen was identified early this morning, and we were able to develop a fix shortly after. That fix has now been implemented on PC and Xbox One in all gameplay regions (and will be in place when Competitive Play goes live on PlayStation 4)."
It's always unfortunate when a bug like this affects a game, especially one with a competitive play mode like Overwatch just rolled out. It is nice to see Blizzard reacting to and fixing the issue in a timely manner, though.