Unclimbable used in a sentence

Unclimbable in a sentence as an adjective

The new route he put up K2 was previously deemed unclimbable by Reinhold Messner and has never been repeated.

People would easily move from iMessage to WhatsApp. Heck, if Google and FB banded up right now to reject iOS out of the blue, iOS would fall into an unclimbable chasm. Of course, that won't happen though.

But all this is irrelevant for the most part because aside from understanding WHY it's useful and important, there's the fact that most people are using web clients, and trying to, say, sign or verify a message in GMail is pretty much an unclimbable mountain for the vast majority of people. Heck, even on desktop clients it's a pain in the ***.

Background: the berserkers developed from communities who for a large part of the year sat on their asses in Norwegian fjordal valleys with an unclimbable mountain range on each side, a lid of horrible grey cloud on top, and you couldn't get away by sea either because of the winter storms. "There's a saying among the Nguni of South Africa that you didn't only have to **** a Zulu warrior - you had to push him over to make him lie down.