Why are flights delayed so often?

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Tags

1. #culprit
2. #takeoff
3. #unloading
4. #spent
5. #preparing
6. #often
7. #passengers
8. #boarding
9. #delays
10. #flight
11. #people
12. #means
13. #number
14. #times
15. #flying
16. #weather
17. #longer
18. #arrivals
19. #which
20. #board
21. #tarmac
22. #caused