What can cause new motor mounts break in 6 months?

I have a Honda crv, the car had some rumbling noise whenever it start moving from idle, my mechanic told me motor mounts are broken and I had them replaced all the mounts ( 3 motors, 1 transmission).

But then less than 6 months later, the left and right mounts are broke again.

And so obviously what they sold me aren't very good quality dispite they claimed they're top quality.

But my question is, even if the mounts are cheap, what are the things that could break new mounts in 6 months?

I thought new mounts should last at least 2 years btw, thank you.

Do not overthink it. Parts fail for many reasons. Get the mounts replaced with factory Honda parts only. If you want to spend some money, have another shop check if your car is misfiring.

Excessive vibration will weaken support structures. I've seen someone attach a thick rod to an engine bolt and then to the chassis to keep his V-6 from moving too much. Look for the root cause first. No modern engine in good working order should be moving that much. Pop the hood and have someone rev the engine to see what's going on. If need be, find a large unoccupied parking lot, pop the hood (remove is better) and attach a camera to record what's going on under engine acceleration with a drive-train load. Get some help from intelligent/knowledgeable people if you do this. I'm not responsible for any sckrew-ups.