Lets say you go in to buy your new bike. You do all the paperwork, and pay for the machine.
Just before you ride away, the salesman brings out a contract. You read it.
It is a guarantee that your bike will reach 70,500 miles, almost trouble free...however, at 70,501mi, it will let go in a big way. You still have to maintain it, and do the two or three valve checks needed, but the bike will see 70.500, guaranteed.
Or, you can refuse to sign, and the bike will last as long as it is going to..basically, the same deal we all get.
Would you take the deal?
I think I would.