That was the reason I changed them. Actually, I changed all rotors and pads twice in the last year for the same problem. I took the car to the dealer and the did not know why it is doing this, othe repair shops question break assisstant system or master cylender but replcing any of those is a furtune!
Just thinking, have you ever heard or felt a vibrating, growling noise while braking in wet weather. Has the ABS or Brake light ever come on, Thinking one or more Wheel Sensors could be faulty during wet weather causing the ABS system to engage not allowing the hydraulic pressure to be as strong as it is in dry conditions, possibly see a bad signal and not allowing the brakes to lock up.
No light up on the dash at all and vibration. the other thing I forget to mention is in wet condition and after I feel that the break is locking enogh, i pupm the brek pedal 2 or 3 times and the break brakes works fine, and continue to work OK as long as i m using the brakes frequently. The problem happen again after long drive for example after long drive on the highway.