Why do accidents happen?

[cascas]

I think the first point is the really key one. Every really good disaster usually has about four or so connected elements. Often times when I decide to dive in definance of something (head cold, poor weather conditions, item of gear broken, etc) I mentally tell myself: "Well, that's the first thing... three to go."

That is exactly the reason why I teach my OW students to "break up" their dive into many short segments and to never take a problem of whatever size into the next segment.
If something is not as it should be, no matter what it is, stop, think, act to solve it before you go into your next segment. No matter how much time you need to do it.
This is something I realy try to make clear to my students and I get really good feedback on that...