Few reasons for Sabres downfall,
- Over reliance on Krakow for technology - KRK has tendency to complicate simple problems and systems in the name of technical excellence which leads to mainframe like systems built in Java (complex, costly to change and maintain, difficult to scale and ramp up). There are many cases where wheels are re-invented at a cost of reliability and scalability.
- Demonising revenue making products and shutting it down to make a way for unproven new products that never makes it to production
- Too much of water fallish approach - pivoting after spending years and millions for something very simple and basic that should have been asked on day 1
- Spending too much on something unrealistic tech products (like NGP) which has no relevance in new era of cloud native architectural philosophy
The list is pretty long, but limiting it for now.