Originally Posted by
ZAGORFLY
Nowadays airlines want to fly higher as possible to save fuel regardless the danger of coffin corner. You may save fuel not lives is something goes wrong isn't?
An aircraft must fly at the optimum FL. If you fly above that FL you will also have a fuel penalty; it would only be economical if you have a considerably increase in tail wind. Other reason to fly above the optimum is to avoid meteorological adversities.
So, why would airlines want to fly higher?