If they are the same nic strength, and same PG/VG ratio, then it's down to either specific flavor ingredients, or just that one flavor suits you and the other flavor doesn't. Some flavors are easier to
vape right away, and some need to rest a while before they taste good. Fruit flavors, for example, are more likely to taste good from the beginning, while flavors with cream or custard tend to taste better after they steep (age) a bit.
tobacco flavors almost always have to steep for quite a while.
Some e liquid companies steep their juices in advance, but some don't and so some flavors won't taste as they should until after they've sat around for a while. Some flavors include alcohol, which can make them harsh to
vape, but after some time, it dissipates and the vape is totally fine.
If you want to say which ones you are using, some people here may have experience with those exact flavors, and can help more!