For the quest Trouble Brewing in Andothren, Nevusa Falen asks you to help her plant a spoiled potion on Hemmette Fauler to shut her business down for good. However, Hemmette Fauler's barter inventory already contains loads of spoiled potions. It's strange that I should have to plant a spoiled potion on her when there's plenty of evidence on her already. Perhaps having a high enough alchemy skill to recognize the side effects of the spoiled potions can allow you to point this out? Personally, the reason I chose to accept the quest was because it felt in-character for my player character to want to shut down a store that sells faulty potions.