H80r1g1n It's odd that this achievement didn't trigger, but one question I have is whether you were playing while signed in at the Main Menu, so you could see your badges (and other online features) while playing. With some achievements, I noticed I didn't get credit for anything that happened offline even though the game should recognize the progress.
If you want to cheat to get the badge (since you've already earned it legitimately), you could use NRaas Retuner to set the length of your preferred type of novel to something short—maybe 20 pages or so—then max your sim's motives through a cheat or mod and let them go to work. I'd suggest a new save just to keep things simple. Let me know if you're interested and need more help with the process.
