The more often you fast charge, the faster your battery will degrade.
Battery manufacturers estimate a number of charge cycles a battery can handle, calculated against the charge rate they recommend you to charge the battery at. Any charge cycle completed at a current greater than the manufacturer's recommendation will cause the battery to degrade faster than that estimate.
It's important to keep pack health in mind, but also to balance it with the actual enjoyment you want to get out of your battery. This is why we recommend fast chargers to only be used when you need to charge fast -- not as a replacement to the stock charger.
If you want to get the benefits of fast charging while minimizing unnecessary battery degradation, only use your fast charger when you need to!
This switching is made easier by variable fast chargers we have available for select products.