No, that would be considered shockingly low. There are about 300 million cars in the US, and it's hard to find good statistics on cars breaking down, but AAA makes about 30 million service calls a year. So AAA alone gets the number to 10%, two orders of magnitude higher. (But I don't mean to exaggerate the difference - Facebook accounts must be significantly easier to keep running than cars.)
I think your math is wrong. 30 million a year means about 82,000 a day ("in the morning"). So that's about 2.7 hundredths of a percent. Another way to independently estimate, is that I've been driving for about 7,300 days and had an alternator failure twice that prevented my car from starting. That's...just about 2.7 hundredths of a percent as well. So I think that 0.1% is 3-4 times higher than normal.
Would you please not be a jerk on HN? This was gratuitous.
We've had to ask you many times about this kind of thing—for years already. Continuing to break the site guidelines is eventually going to get you banned. I'd rather not have to do that, so if you'd review https://news.ycombinator.com/newsguidelines.html and stick to the rules when posting here, we'd be grateful.
Enough to employ people to look into the problem(s) and fix them?