A recent story I have been fascinated by involves the Android reader RedditSync - not OSS, but championed by a fearless Solo Dev. He released V20 after so long and so much feature feedback from dedicated users in the Play Store beta channel. Immediate community revolt from V19 users who just liked the UI the way it was and never new there was a beta program in the first place. Much subreddit infighting. Rollback. Cooling off period. Now its basically forked with X users on a 'beta'V20 and Y users on the Play Store V19. [1]
Honestly my heart goes out to the dev who solid knocks out feature requests and just didn't expect the level of cling his old UI had developed. Some people were proper angry and he was in a tough spot.
Anyhow its probably better material for a business school case study but point here is even a one man project can get caught by UI pattern bias.
* Code is more interesting to the author than user experience
* High familiarity with a tool, as authors gain by working on a tool, will normalize bad UX
* Free software (specifically) often attracts a type of person that has very non-mainstream UX tastes