&#x27;Let it crash&#x27; is a philosophy geared toward handling errors.<p>Circuit breakers are geared toward handling resources that may become unavailable.<p>While they seem similar, they&#x27;re conceptually very, very different. Let it crash is mostly for things where one&#x27;s own code, one&#x27;s own state, may end up faulty, and where recovering in a known good state will solve the issue. And it turns out this is really effective for most &#x27;bugs&#x27;.<p>A circuit breaker is where -external- state, environmental state if you will, may become faulty. This is really effective not for &#x27;bugs&#x27;, but for predictable periodic issues such as one&#x27;s network going down, a database becoming inaccessible, etc.<p>Everyone who writes a reasonably complex system in Erlang, that interfaces with systems external to it, learns the shortcomings of applying &#x27;let it crash&#x27; to those instances (a network hiccup overloads your supervisor threshold with crashes, leading to parts of, or the entirety of your system going down), and goes looking for (and hopefully finding) the circuit breaker pattern.