One-time arrivals are between 70 to 80% these days. Which means that if your round trip has a single stop (4 flights to go and back), one of them is likely to be delayed. Which means that you will miss connections/appointments in almost every tight trip.
Discussion
Also travel time per leg already includes so much extra taxi/dep/in route delay/arrival/taxi time that the 70-80% on time metric is a scam to begin with.
Hum.. does that mean the real number is better or worse?
Worse! Lots of extra time packed in to those flights. That’s why you almost always arrive early when you leave on time.
I had 3 hours layover.. still missed it.. 😔