WileyB
Eddie Richenbacher stressed "Reliability" of air transport back in the 1930s. His backers understood that this had to include the then new technologies, Radio Range etc. Others understood that any mishap, and that included off- schedule operation, costs money and ultimately insurance premiums would rise.
"Safety is no Accident"
Newer aircraft became larger, faster, and more productive, and must be kept working to repay their initial cost. And they became more efficient. Staff need suitable training, to get the best from the Capital - it is an investment. Reliability encourages profitability.
( Just think of re-equipping AF with Constellations to do its present work. In 1970 I replaced the fleets of one airline with 400 Yorks, which would not have been subject to Night Jet bans ! )