Nissan Micra breaks changed twice in 45k KMs

I bought a brand new Nisan Micra in October 2018. Since then I've been told I have to replace break pads and discs twice to the total combined value of R12000. I keep asking how a car that's on 45000 kms can be changed breaks twice already as the service consultant himself said the life of breaks is about 30000 kms, I was told that it's how I drive. The car was parked literally most of the time in 2020 due to Lockdown and working from home. Can someone explain how this is at all possible? I bought a brand new car so I wouldn't be having to cough up money for parts so early.