Complex systems are always in a state of maintenance. Some part is
always failing, but we can repair it. Systemic failure happens when we
can't keep up with the necessary maintenance. It's very easy to look a
a big complex system, see lots of failure, and conclude the whole
ship is going down, but that may not be the case.
Funny thought: then we may characterize a complex system as a system that's (most of the time) too big to fail all at once, and whose resilience to failure simply arises from continued previous failure. Which sounds like another way of saying "I don't know what I'm doing, but it kinda works"... until it doesn't. Maybe when it has inevitably grown too big to be successfully maintained anymore.
But "failed state" simply means that some of the controls have been disabled, at least according to John Gall. That just translates into working without quite knowing how they work.