Actually, to give Bowser some slack, I have never seen anything that indicated that any of the structure of the WTC was specifically designed deliberately by the engineers with eventual collapse in mind, i.e. deliberately built so a major failure would cause it to come down vertically. I would be glad to be corrected on this.

The design documentation I've seen implies rather that it was built not to come down at all, with many structural backups. The fact that its plane collision specs--and it did have some impressive ones--were developed in an era of considerably smaller planes was its apparent Achilles' heel. There is some controversy over the switch from asbestos to less-effective fireproofing, but I have seen nothing firm in that area one way or the other.

It's possible that any tall building with a largely exterior structure like the WTC may not be likely to physically collapse any other way, but I don't ever recall seeing anything in an article that suggested that this was anything other than luck.

As for entropy, had the day come when the WTC had to be dismantled--and I can't think why this would happen--it most likely would have been dismantled from the top down piece by piece.