Cracked, on the other hand, is very good at talking about math

I tend to avoid Cracked.com. Their articles are thoughtful, informative and enormously entertaining. They can discuss complex, even technical subjects in a clear and engaging way. All of this makes the site a dangerous time sink and I just can't afford to hang ouot there.

From 6 Small Math Errors That Caused Huge Disasters

#4. A Huge Walkway Collapses Due to a (Seemingly) Inconsequential Design Change

When designing their newest hotel to be built in downtown Kansas City, the fine people at Hyatt Regency wanted all the bells and whistles in it. The architectural firm in charge of the building design came up with a series of aerial walkways suspended from the ceiling so that guests could people-watch from a heightened vantage point. All in all, it was a pretty nifty feature. Until it suddenly collapsed and killed more than a hundred people.

The Laughably Simple Flaw:

One long rod was replaced with two short ones.

If there's one principle consistent across all human nature, it's that we will always prefer the path of least resistance (i.e., "if you can get away with a half-assed job, do it"). The original plan was for two walkways that were directly on top of one another to both be supported by one very long rod that would anchor into the ceiling. Like so:

Easier to work with, easier to install, works exactly the same. Right?

That little change killed 114 people, injured 216 more and cost $140 million in lawsuits.

Look at the first image again.

One rod, two nuts. Each nut only has to carry the weight of its own platform. Which is good, because each nut (and the welded beam it's screwed to) is only rated to carry the weight of one platform.

Now look at the second image. See the nut we've labeled "OH SHIT"?

That one single nut now has to carry the weight of BOTH platforms, and all the doomed tourists standing on them. Look obvious? Congratulations, because none of the professionals at either company caught it.

And so, one night during a dance competition, the stressed "OH SHIT" nut cleaved clean through the beam and the walkways collapsed.

During the ensuing lawsuits, it came out that neither the steel company nor the engineering firm in charge of construction had even bothered to do a back-of-the-envelope calculation that would have shown them this glaring flaw.