I had a similar observation as the OP but mine was due to spring training. I used to have a varied assortment of players I'd bring to spring training. And as it was over, I'd send people back down to the minors depending on their level, age, potential, etc. Every single one I'd send down, whether it be AAA or lower would be unhappy for the full season and beyond. Now, when spring training comes up, I only bring my anticipated ML roster and skip thru it to opening day rather than play thru it (which I used to do to learn about players and try out different lineups).
I guess as one person said, I could turn off morale but it seems like a neat feature and I like seeing it. Kind of reminds me of Tropico or a number of rpg's where we could look at people's morale and try to change it. But here, it just seems if a person is moved to a lower league, nothing short of promoting them again will ever work.
Maybe I'm doing something wrong and someone can guide me to do it another way. Thanks OP for letting me piggyback onto your question
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