This is just a warning for anyone whose sim is in the art appraiser career.

My sim is a master forger, and along the way to getting there, he completed the advanced art training opportunity offered through the career's rabbithole. I've found that, when completing the stage of the opportunity that lets you paint brilliant paintings on command, and again when completing the stage that lets you paint masterpieces on command, my sim loses one of his six traits, dropping to a total of 5. He doesn't lose his rebel influence trait; he loses one of the standard traits. He lost "excitable" both times.

I'm curious to know if anyone else has had this same experience, or if it's just me.

I don't know why this happens, but without a doubt, it happens to me immediately upon completing these opportunities. I assume that a sim with only five traits will not drop any traits, but since you need to be at level 10 rebel influence to even get the art appraiser job, chances are your sim will have at least 6 traits, 7 if they have a degree. With mods, you can easily just give the trait back to your sim using Master Controller. Without mods, I assume that you can use the "midlife crisis" reward to add the trait back, but I haven't actually tried it.

I still love this opportunity chain, though - especially since I was able to fix the damage.