There are several reasons why we see the same problems with an evacuation, time and time again. This actually appears to be quite a good one , with few injuries and the crew seeming to do a textbook stop on the runway. Most of these have almost been done to death on this thread but once again I feel that the biggest threat to safe operation is the dreaded "Bottom Line".....MONEY
From the moment PAX get on, they are bombarded with PAs to buy this or that and consequently the Safety Demo PA can be lost in the background as people just try to block out the ambient noise. The time spent on the briefing has been shortened by many operators to make sure the aircraft departure is not delayed at the holding point, and the cabin check is performed by the minimum number of crew that the company can get away with by law. THis means that an aircraft with 8 emergency doors/exits can operate with 3 Cabin Crew members.(ratio of 1CC to 50 Pax) Are we all happy with that? Also from my experience, when one starts selling emergency exit seats as an ancillary cost, the true meaning of "Able Bodied Person" seems to get lost in translation for that extra £10. If I had had to open the overwing exit last week, then the person I was sitting next to who was also in an "extra legroom seat", would have acted like a plug and not an ABP.
I certainly don't blame "Jean" per se, but safety costs money, and people appear to be willing to accept reduced margins for a cheap ticket. I guess that's the "Bottom Line".