Motor are not spinning properly

when i arm the vehicle motor a and motor b are spinning.
when i give the throttle motor c is spin.when i give more throttle then motor d is spin. so why the motor are late spinning when i give throttle.

You probably did not calibrate the escs or your MOT_SPIN_ARM parameter is too low.

Either way a Methodic tune with the Methodic Configurator software would have avoided the issue