Purely conjecture on my part but I think I only get a few days between cleanings due to
how I vape. I bought out a members stuff so I have both new and old style, pre-fill and blanks. They all seem to get weak after a few days.
I am off the anologs 3 months now but off the smokeless tobacco 2 weeks. To get anything resembling the nicotene hit I got from the dip, I rarely take a hit that doesn't reach the cut-off. I also chain vape and keep the coil smoking, literally. The few cartos I have rebuilt took quite a bit of coil dry burn to clear the build up.
Since I never vape anything thicker than pg80/20vg, I am guessing I am choking the coil off in a few days by keeping the coil scorching hot and carmelizing the juice more rapidly than it would normally. It works for me though and I have no complaints. I have yet to get a burned carto or filler but I do keep them wet with 4-5 ML a day.
I doubt many are the fiend that I am while still killing the Copenhagen urge but I am wondering if the vaping habits of others who may take repeated hits in a short time may be effectively doing the same coil clutter as I am. I only see one other vaper in person and I have noticed she tends to press the button a full second or two before she takes a hit.
I can see based on my findings while cleaning how the extra heat generated by rapid and long duration pulls might cause a performance degradation more quickly than a normal vaper. And it may be a bad batch as others have surmised. I just know the GO-GO and carts gets it done for me so my only complaints relate to hardware quality or lack there of. The vape itself is great.