What are refillable e-cigarettes?
It is the compromise for lazy people who still have a shred of conscience. You keep the battery and only change the pre-filled (or refillable) cartridge. It is cheaper and less polluting than tossing electronics every time you finish a bottle. It is vaping for the responsibly lazy.
Technically, these are closed or semi-open systems. The battery recharges via USB-C. It is the logical step to leave total disposables behind without fussing over complex builds. It is more economical, cleaner, and most importantly, still allowed by the authorities.