Your LeCig Cartomizers, as we're sure you're aware, are filled with a special liquid that vaporizes when heated by an air-flow activated battery. Now, in order for this to work, the liquid must be contained in some sort of suspending agent - in our case we use a sterile, synthetic poly-fill material.
As long as the poly-fill material remains sufficiently moist the flavor remains consistent and strong. However, there is only a finite amount contained within each cartomizer, and when it begins to run out you will start to taste something ever so slightly burnt. When you notice this slightly burnt flavor that’s your indication that it’s time to refill your cartomizer.