That's because you are rewrapping with cotton. Granted if you are using Japanese cotton you will see better results. But cotton like any other type of fabric type material absorbs and gums up fast as a rule. With the silica coils seen with the Atlantis I can swap out flavors with each tank fill and only wait for the little of the previous to dissipate before getting the full flavor of the next.
For cleaning with the eventual tendency to gum up I simply drop the small gathering of used coils into something like a travel mug with cover and soak the coils overnight in warm water with a denture cleaner. Some will use rubbing alcohol which I would veer away from since Efferdent will do the job and rinse much easier.
Since the first vape back in Sept. 2012 with the disposables first tried moving on fast to the Bloog cig alikes and finding blank refillable cartridges and later 1.6ml top coiled by them as well as for the Vamo and first eGo batteries the need to swap anything daily would be either one blank worn out fast as expected or the need to soak the long wicked top coiled crap to avoid the burn spots from dry wicking issues commonly seen! The first larger tanks bought for the Vamo V2 were leaky as all H DCT type DCT being the old 510 type of insert or threaded cartimizer you dropped into a tank. The second of those had a locking seal washer type ring on the bottom and still leaked like a sive!
With the mech you end up having the need for high amperage batteries and keeping the resistance consistent while the premade do offer the consistency out of the box. The problem typically seen with the older pre-sub ohm type tanks were obvious as far as lack of vapor production which can also very much damper flavor production forcing people to look at other options and why RDAs took right off! The market being flooded with cheap tanks certainly didn't help any either.
With Smoktech they do have some great stuff at times while you still need to watch for the not so good as well. With Vision the outcome going from the top coiled 1.6ml to the Victory BCC type was no joy as well as other tanks like the SMOK Trophy and Eleaf by iSmoka IClear series that failed on vapor big time whlle the SMOK Tumblers work out well except for the short lived coils. And this was the main problem seen too often.
While many rave about Kanger in contrast Aspire set the pace last year between stepping up with the Nautilus and later Atlantis with the much better coils with the later setting the current trend being seen with all types of imitation and all styles of sub ohms arriving. Some of those however not too good!
And that simply brings many back to rebuilds and rewraps. Have been seeing some interesting rebuilding stations that are sure to noticed lately.