I have no idea. This whole conversation seems like a big tangent, and perhaps I'm having a bit too much fun following it off into infinity. Shame on me.

Anyway:

Yes, Boeing has a more difficult task than many startup founders. Of course, there are also more engineers at Boeing, and they've been working on the problem for a much longer time.

Yes, it would be possible for a Google or Facebook design error to get someone killed. Leaks of personal or financial information are potentially deadly. Bad information can be deadly.

No, I can't give you a specific example of a design error (as opposed to a user error) that killed a Google or Facebook user. That's partly because Google and Facebook engineers -- like Boeing engineers, and most engineers worthy of the name -- take their work seriously and don't make many consequential mistakes. But mostly it's because our standards are looser, and reasonably so: The internet is a twelve-year-old invention, and when planes were twelve years old people crashed and burned all the time. They were experimental, and nobody expected anything different.

Standards will change. We're hearing stories of users who followed a Google map off a road and are now suing Google for damages. Right now those stories serve as hilarious examples of lawsuit-happy, stupid people, but perhaps in fifty years middle-class people will expect digital maps to be perfectly accurate, just as today they expect to have clean water and lead-free plumbing, and to always be able to reach an operator by dialing 911 on their cell phone.

Finally, I don't think this sentence is correct, in general:

The fact that people misuse something doesn't make it the engineers fault.

The problem is that there's no bright, shining line. Your kitchen knife example is far to one side of the line: Because kitchen knives are a very well-established technology, most knife accidents are caused by people misusing the product. On the other side of the line is, say, food that's been sweetened with ethylene glycol. That's pretty obviously a design error. And in between is a huge grey area, in which most software falls. Is Boeing responsible when a confused pilot pulls the wrong lever and fails to lower the landing wheels? [1] Is the guy who built the buggy online spreadsheet responsible when the civil engineer uses it to design a bridge that falls down? Well, that's why we have courts -- and why your startup needs to have a lawyer.

[1] I do know that planes used to have a little wheel-shaped lever to guard against this very problem. Maybe they still do. I forget where I learned that -- was it from Donald Norman?