The implicit assumption behind this statement is that using production for testing increases the risk of production outages. Even if we consider it correct, I

The implicit assumption behind this statement is that using production for testing increases the risk of production outages. Even if we consider it correct, I think it is a mistake to believe that the only way to handle that risk is to open the environment proliferation can of worms, and jump inside. It isn’t. Each system is different, but in the vast majority of software systems I have found, concerns with testing on production environments aren’t actually good reasons to use non-prod environments. They are instead signals of more fundamental flaws in the system itself (or in the dev practises). To use an example. If we are talking about a multi tenant system and we worry that tests ran against the testing tenant can break other tenants, what we have is a system that is inherently broken. We don’t prevent this problem by doing tests elsewhere (and inflating the maintenance burden, creating the risk of divergence between test/non-test envs, etc.) We prevent this by implementing multi tenancy correctly.