[WWKong]

"Isn't the ethos of Silicon Valley to 'hack it together' with tape and glue?".

That explains the low single digit success rate. And that is not really the ethos either. It is mostly a translation of lack-of-experience.

Silicon Valley is a business arrangement. Some folks have money which they spread over a bunch of high-risk/high-return investments. They net out positive. What we get is handful of mega successes, tons and tons of failures, lot of marketing noise, opportunity to work on some cutting edge experimental stuff. It has a mix of people living well (which we hear about) and people who endure bad living conditions.