brakes are like consumables wear/replacement at 15000km doesn't look odd to me . brake wear depends upon driving style and type of environment . brake pads last more at humid atmosphere and wear out fast at dry and sandy areas.. morever brakes are highly safety oriented parts and early recommendation for a change should be for well being. technically, stiff brake pad materials which do not wear fast will wear out the brake discs which is highly undesirable but bit more softer brake pads gives better friction hence better braking. i find my fiats brakes highly effective and reliable compared to most of other brand cars and i am happy with it too.