You can have a bugfree code, but release it in 6 months. Or you can have a code that creates outages once per month, but release it in 3 months (figure of speech, 6 months is optimistic for some projects).
By trying to optimize for 0 bugs, you are losing on the 3 month of business opportunity of high revenue. At FANG scale, that's a lot of money.
Disclaimer: G employee, but this is my own opinion etc.
That said, no one (in their right mind) intentionally releases buggy code. They may release incomplete or under-tested code, of course. But that's not what I'm talking about.
I'm saying that when someone feels like they're "done" (in a reasonable amount of time), some people will end up with more bugs than others. If the trade-off is 3 more hours of work for 1 fewer bug, that's an incredible economy.
And, of course, no metric is perfect or comprehensive. But "bugs per hour" is much better than LoC per hour.
Not directly about development, but this should be somewhat of a rule of thumb in general: https://www.slideshare.net/dmc500hats/best-strategy-is-speed...
Time is important. More important than you think.
The same is true of number of issues closed. Some issues are short and quick, and some issues take a whole day. Sometimes an issue will seem small and turn out to be large. Handling these things is part of good management.
I personally measure people more on how many bugs they don't produce. A single bug can cause losses of revenue that are equivalent to weeks of a developer's time. Bug-free code is so much more cost-effective than fast code.