Because it seems like I'm having to work twice as hard, and take a much tighter, longer draw, and still vapor is minimal. I mean, it still works, just not near to the level I was. It is impossible to go back to the carto I was using before, because I was trying to adjust my tank the other day, and the whole filler just came out, still attached to my pv, and the tank and carto sleeve slid off still attached to one another. First time that ever happened! Idk, I switched from punching my own boges to using prepunched smoktechs with a flanged bottom, and that first one was good untill the whole pulling out of the filler mishap