If I get a liquid that has an alcohol, chemical or perfumey smell to it, I'll take the caps off, leave it in a dark cabinet for a day or two... shake it up a couple times each day. If the smell is gone, I cap it, maybe try out a little. If it's good, vape it. Some flavors do take a bit longer to have an optimal taste.
Most of mine are good from the get go. I like sweetish creamy flavors. I hear that tobaccos, chocolates and some
dessert flavors take a longer steep time. Like, up to a couple weeks with some.
Basically, if it's not to your liking in that time frame, it just may not be for you. Everyone is a bit different in this. Some people even "speed steep" using different methods.