Still a very good question though. Michael considers it one of his first really well written songs so to use them for the Jacksons project is quite odd especially after his breakthrough with Off the Wall.
He then later did the opposite by not releasing his best solo work for Victory (Liberian Girl, Buffalo Bill and possibly Dirty Diana?)
A case could also be made for Be Not Always unless Marlon takes most of the credit for that song. It is probably also a bad example as it is one of his least popular songs (based on Spotify streams) so if the fans consider it a throwaway, then maybe so did Michael at the time?
It would have been interesting to know about his thought process but unfortunately he was never really asked questions about things that I find very interesting lol