He couldn't test for longer, so it's not expectation of short lifetime, but stated limitation of the test. Plus, there is a very high expectation of having a m

He couldn't test for longer, so it's not expectation of short lifetime, but stated limitation of the test. Plus, there is a very high expectation of having a material that is pleasant to touch, easy to grip, but is extremely hard, does not shatter and does not scratch even on a micro level.