Why a relative replaced some perfectly good Michelin Tires?

Had bad sidewall cracking issues on Goodyears. Never buy that brand again. Now have Michelins, and had to have a patch after 4 years of use. Tire place warned that the sidewalls were starting to show cracks.

Now I read this stuff on tire places not servicing older tires...

Guess buying tires with 60000-90000 mile treadwear warranties is pointless unless you use it as a taxi or something.