All most people need is a few near misses by tropical storms or hurricanes and they convince themselves that they can ride out a hurricane, even a potential Cat4. Reports are that by the time many became sufficiently concerned, the shelters and hotels had filled up. Then there are people unwilling to abandon their possessions to the storm. I saw several pictures of evacuees carrying big screen TVs to a shelter. This part of the Gulf coast is not an affluent area, there had to be a large number of people who made an economic decision that they couldn't afford to travel and stay out of the area.
If you live in hurricane country you need much better tools than the bubble-heads on TV, or that goofy Weather Channel. This hurricane was strong, but compact. 100 miles to the northwest of the track provided by the National Hurricane Center would have put you well out of danger. That isn't me saying so, it was a reliable fact of the known track. And in the end, there was nothing the people who stayed could have done to protect their homes. They just became a liability for the responders who were called to rescue them.
In the days to come we will see pics of shocking devastation. Whole buildings gone from wind, tornado, and surge. But right now the tree damage and wires down are blocking media from documenting the damage.
My parents rode out H. Hazel in 1954, partying with friends and enjoying the day off from work, my mother pregnant with me. Afterwards they had time to reflect on their great good luck at not being trapped by it's 20 foot surge. Scared them silly. After that my dad never again weathered a hurricane in place. He always evacuated early. When I rode out H.Irene in 2011, aboard and outside the track, dad called me every hour checking on the situation and requesting that I show some good sense and step off to higher ground. He was right of course, when the winds went over 90 mph I could no longer get off safely. It made him angry that I had taken such a needless risk.