I've noticed that too. I think there are a couple of reasons why disposables might seem to have a better flavor.

First off, disposables are designed to be really convenient with everything, including the coil and wick, optimized for the specific e-liquid they contain. The manufacturers basically fine-tune everything to work perfectly together, which probably helps in giving you that intense flavor right from the start.

Also, disposables tend to use fresher coils since you get a new one with each device. Coils in reusable vapes can get worn out or gunked up over time, which can mess with the taste a bit.

The type of e-liquid might also play a part. Since disposables are meant to be used up and then tossed, the companies might opt for stronger, more robust flavorings to make them appealing right away.

Of course, this is just from what I've noticed and read up a bit. Would love to hear if others think the same or have different views!