Coil only needs replacing if it breaks/fails or gets mangled...........or if you want to try something different.
When ever doing a wick change:
Rinse wick
Twist out of coil to prevent coil stretching
Check coil fastening screws - they can get loose over time
Pulse coil to heat and burn off Gunk
Cool coil and rinse off Ash
Recheck coil function(glow from center out)
Adjust individual coils if needed
Check resistance
Install fresh wick
Wet wick(
e-liquid) and test fire
Recheck resistance
finalize assembly
Recheck resistance
VAPE!!!!