It starts with GA pilots being very conservative with what kinds of planes they invest in, since planes are huge money sinks already. The old engines have ver

It starts with GA pilots being very conservative with what kinds of planes they invest in, since planes are huge money sinks already. The old engines have very well characterized reliability and cost, so pilots know what they're getting into and can accurately plan for all their expenses. New planes/engines are proposed fairly regularly, but generally fail because there are too many unknown factors that buyers are wary of.