I encountered this quote while reading Martin Klepmann’s Designing Data-Intensive Application which got me thinking: A complex system that works is invariably found to have evolved from a simple system that works. The inverse proposition also appears to be true: A complex system designed from scratch > never works and cannot be made to work. John Gall, Systemantics (1975) This is a famous “law” in software engineering. (although the original context in which the author said this is in regards to general systems (mechanical systems like Titanic ship or human systems like an organization; come to think of it, even software systems are just an extension of such systems).