RE:RE:RE:RE:2018 Breakout YearAgreed. That's no contradiction. Individual airlines know the benefits of having a consistent fleet. But when it comes to upgrading to the next plane they want competitive choice. Hence multiple suppliers.
Same for the plane makers. I worked in the railway industry. We went out of our way to encourage competition for everything - radios, engines, track, etc. We worked to ensure that no one had a future monopoly.