[m0llusk]

The biggest differentiator may be the infinite length of tracks. Once you tune into something that fits it can be left going as long as necessary. With other services there is a need to compose play lists or restart the player when a selection ends.

[NoGravitas]

There are plenty of 10 hour ambient tracks on Bandcamp. I personally recommend Iron Cthulhu Apocalypse for this.

[XCSme]

Most services have a "radio" station based on that song/genre that gives you almost endless listening time for that type of content.

[m0llusk]

Such offerings have discontinuities between tracks or beat matched transitions. These generated tracks are constructed to continue with the same themes and sounds as long as wanted. It may or may not be desirable, but it is different.

[XCSme]

Oh, this makes sense, I didn't really think of the transition as potentially being distracting or a cue to stop working.

I personally use a "relaxing music playlist/radio", the songs are pretty similar (meditation music), and I don't often notice the song changing, but I do often notice that suddenly I am listening to a completely different melody.

[gffrd]

… but there's no continuity with radio … or not a uniform/dependable continuity, at least: the mood is different song-to-song, and there is no control over the "levers" beyond _skip_ and _like_. So, to "train" the radio stations involves interacting with them.

What if I just want to "set it and forget it?"