Yeah, some
e-liquids can drastically improve. Just try the liquids when you get them. If they taste good, no steeping needed. Lots of liquids that I ordered tasted good out of the mail, but I think that is because some were probably pre-mixed and sitting at the vendor's location for some time. I guess some liquids might not need steeping at all, but I really think that most do, and we just don't realize it because the juices have already steeped before we get them.
When a
juice doesn't taste good at first, leave it alone awhile, in a cool, dark place as others said. Saying that they have a chemical and/or alcoholic taste is pretty accurate with my experience, it's hard to describe but not pleasant. But, I tried them after a few weeks, and after steeping they definitely tasted better.
Cake Batter from Vaperite is one example I can think of. When I first received it, it tasted strange and chemically, not something I wanted to
vape. After steeping, tasted really good, exactly like vanilla cake batter with a buttery sweetness.
On the flip side, I noticed that some juices have harder throat hit right when you get them, and I think the nicotine level slowly decreases over time, which slowly reduces throat hit.