Nothing is wrong with the flavor oils, flavor oils are just fragrance oils that are lip safe. Unless they have sweetener added, then they will just taste bitter, all of them I have are like that. Just add sweetener and the lip balms will taste better. I personally don't like sweeteners in my lip balms because they make you lick your lips too much, therefore resulting in dryer lips, so I just add the unsweetened flavor oils. Never had a complaint.