Chains usually have no service interval, so at the outset they seem cheaper and more reliable. But the unfortunate reality is they still fail, or something related to keeping them on fails, you just live in a false sense of security for a few 10's of thousands of km more

The good old “lifetime” part. Just like the “lifetime” fluid in most newer automatic trans.

And since they're not meant to be serviced on a regular interval, they're designed that way too. A timing chain might be over four times the expense to replace when compared to a timing belt, but possibly without actually lasting over four times long.