Tire RETREADING - why it can't be done?

Hi
i wanted to get the tires replaced in my honda car -10 yrs old.
i asked if the tires could be retreaded. But was told it can't be done. And he mentioned some term that i can't get.
what are the reason a tire can't be retreaded.
i'm referring to MICHELIN tyres.
how much would be a saving between retreaing in stead of replacing the tire with a new one.

Retreading is rarely done on passenger tires these days due to liability and cost inefficiencies.

If you're too cheap to buy new tires, then buy used ones. Look for used tires in your area on google.

It was done on car tires years ago, but now is only done on larger tires.

Modern passenger tires can't be re-capped. Commercial truck tires only. They aren't built the same way.

Since modern passenger radials can't be re-capped you save nothing by doing something that can't be done. I wouldn't trust a tire carcass more than 10 years old anyway.