Ask HN: How does high quality source code from Google looks like?

There is a lot of content out there regarding high-quality source code to write maintainable and clean code. This is not what I am looking for.

Every now and then, I read answers from Ex-Google Engineers on questions like "How is it like to be out of Google? What do you miss in the industry?". Often they say "the quality of source code".

I am curious: What is that special to the source code inside Google? What makes them "high quality"? Is it a well-commented code base? That people with less context get a grasp of what the piece of code is doing? Is it a strict following of company-wide coding guidelines? Is it the tooling around that supports the maintenance of the quality?

I am curious to hear answers from people who have experienced the code inside Google. And maybe have concrete examples?

Thanks all.

Thanks!

I am a huge fan of Go. My question here would be more like: Is this comparable? A lot of people outside of google contribute to Go. Are similar standards applied to the Go Review Process like to internally created software?

I think it says a lot more about how strict the readability standards are for submitting stuff to corp/production. Even code written by a moron by me looks decent after code review.