Comment by aqueueaqueue

This is less a question of perfection and one of trade off's. Laws of physics put a limit on how efficiently you can keep data in NYC and London in perfect sync, so you choose CAP-style trade-offs. There are also $/SLO trade-offs. Each 9 costs more money.

I like your example it is very interesting. If I get to work on (or even hear someone in my team is working on) such interesting problems and I can hear about it, I get happy.

Interesting problems are rare because like a house you might talk about brick vs. Timber frame once, but you'll talk about cleaning the house every week!