For example, a band like Joy Division. Two masterpiece albums in the form of Unknown Pleasures and Closer, and the untimely death of Ian Curtis cut it all short. They were even heading into the direction that New Order eventually went in, and it would have been interesting to see what Ian Curtis would have done if they fully made the leap into electronic music while he was still alive.
Frightened Rabbit. Good body of work still but would have loved to see them keep going. Their music really hit close to home. Plus I only learned of them several months after Scott Hutchison’s suicide. What could’ve been.
+1 - I recently re-listened to all of his albums while creating karaoke versions of them all (here in case of interest: https://www.youtube.com/playlist?list=PLjPVqMYwkaP4zaPCEhTfkTyRspxoOyjfY ) and it made me sad to think how much of Scott’s reality was actually coming through in his lyrics.
Mother Love Bone: broke up before they’d released their first album. RIP, Andrew.
Also, School of Seven Bells (RIP, Ben)
Slint. They broke up before dropping one of the greatest, most influential albums of all time.
The death of Mark Sandman (such a great name) on stage, 24 years ago, brought an end to Morphine. No other band can match the imagery and atmosphere of Noir as well as they could. You could also feel the evolution of their sound from their last album The Night.
Can we include Trevor Moore in this discussion?
2 albums of music in addition to the wkuk (which had songs as well)
Story of out times
High in church
The Civil Wars. Apparently, they has a falling out and split up. Too bad, both are very talented.
Traveling Wilburys. I know a supergroup of old guys is kind of cheating as an answer to your question. But it’s a shame they weren’t able to record more.
They never did release volume 2, only volumes 1 and 3. So sad.