If using PWM you would use these (default) values:
MOT_PWM_MAX,2000
MOT_PWM_MIN,1000
and if using DSHOT (preferred) then those PWM values dont matter.
In both cases you use the MissionPlanner or QGC motor test to check and set: MOT_SPIN_ARM
for the lowest reliable start-up of all motors.
Then you set MOT_SPIN_MIN by adding about +0.03 to the ARM value.
MOT_SPIN_MIN needs to be high enough that motors wont be stalled or reversed by fast descent, but low enough that the copter can easily descend (and not keep ascending).