In systems that are both interactively complex and tightly coupled, small independent failures interact in ways no designer anticipated and propagate faster than operators can intervene — so accidents become a property of the structure, not bad luck.
Then
Reduce coupling — add buffers, timeouts, bulkheads, and circuit breakers — and cut complexity before adding more safety interlocks, which themselves add interactions.
Unless
High-Reliability Organizations — culture, slack, and decoupling measurably beat fatalism
Perrow put systems on two axes. Only the top-right quadrant produces accidents nobody designed and nobody can catch in time. Both axes are yours to move: decouple with buffers, timeouts and bulkheads, or cut the interactions. Adding another safety interlock moves you the wrong way on the horizontal one.