Bearing failure

I replaced two wheel bearings on a car and both bearings failed at the same time.
I had to examine what happened ,these were sealed bearings and the work was carried out in the usual way with a press and dollies. The work went well and the wheels turned with out sound and were verry free. drive test showed no problems and the car was released to the owner. I did follow ups on the car and all was well.
Nine months later the bearing started to hum and I knew there was a problem.This noise has got so bad vibrations could be felt in the steering wheel. the car was taken to another person to have them replaced.
I asked a friend of mine what would cause such a failure, his reply shocked me! He had two bearings go at the same time and he put it down to cheep knock off bearing from china with all the marking of a good bearing. They were bought from a trusted source and when his bearings failed they snapped the axils with expensive replacements of not only the bearings but also the axils.
Australia needs to up date the laws or someone will die from this.
Some years ago I had a grease gun explode and reported it to the labour industry and they wanted to fine me for not using a reputable brand. Forget the safty aspect that was never an issue to them.