So I understand the general concept going on right now of labels or artists witholding new releases from Spotify, and waiting to let actual album sales die down before making them available on streaming platforms. However, I've come across a few curious cases of old music not being on Spotify that almost seems like an oversight. Two examples are the album "Soul's Aflame" by O.A.R., which was their second album, and their first album is on Spotify, as is every album after. The other I've come across is Marc Broussard's "Carencro," which again, is his second album, and all his other material is readily available.
In both cases, those albums are available on other streaming services like Rdio. I don't know what Spotify's process is for uploading albums, but is it possible these albums were somehow just missed? Or is there some strange reason they have not been made available?