Charity Majors:

it’s actually an unqualified good for engineers to be interacting with production on a daily basis, observing the code they wrote as it interacts with infrastructure and users in ways they could never have predicted.

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A system’s resilience is not defined by its lack of errors; it’s defined by its ability to survive many, many, many errors. We build systems that are friendlier to humans and users alike not by decreasing our tolerance for errors, but by increasing it. Failure is not to be feared. Failure is to be embraced, practiced, and made your good friend.