keeping errors at zero does not mean errors don't happen, it just means you resolve them all, you don't ignore any. Perhaps it should be 'keep errors at 0 or 1'.
So if you're small, a RAM issue is something you deal with manually and rarely. As you get bigger you'll transition to automated failovers that still get looked at individually. Then you'll scale up to the point where these aren't freak occurrences. Now its important for you to have a strategy to identify the issue and its follow on issues, and resolve them. Its also past time you think deeply enough about your setup to be able to contain them so you can stop surfacing them as errors - they are now part of a normal business process. You want to make sure that too many are surfaced as an error (and too few), and any effects you can't currently recover from automatically are also errors.
Its perfectly possible to "keep errors at 0" without ignoring any output.
Okay, how do you handle a network failure, a full disk or a faulty RAM stick?
I see your overall argument, but at some point you've got to accept that you can't handle everything.