Well I would beg to differ. The entire design of the airframe and engine is based upon 'containing' engine failures.
Obviously the QF example is in the extreme, most engine failures are not overly dramatic. Infact the entire premise of ETOPS is based on their being an acceptable risk given that there WILL be a number of In Flight Shut Downs (IFSD).
I am just saying that given a number of indications that may show the engine in question was not operating normally it is quite acceptable to continue with that engine in service as long as all of the indications still fall within acceptable parameters. I have taken aircraft that may show a higher than normal oil consumption, or indeed one a few weeks ago that needed to be checked at the start of every flight day due to debris being found in the oil. If we were so worried about all engine failures resulting in QF like damage we should be grounding aircraft as soon as engines show any signs of abnormal operation. We don't do that because it is not always a given that an engine failure will occur and even if it does chances are the actual 'failure' won't result in any damage or put the aircraft in any imminent danger.