Before Google came along and showed the business people the benefits of horizontal scaling, any software engineer would be automatically considered crazy if they suggested an architecture that wasn't built on a central RDBMS.
So you have to weigh it against the other cargo-cult. How many startups along the way have failed due the inability to scale horizontally?
How many have failed due to too much cost and complexity associated with re-engineering an architecture in which the assumption of fully ACID transactions permeates the entire codebase? (While the phone is ringing off the hook because production systems are falling over under load.)
Before Google came along and showed the business people the benefits of horizontal scaling, any software engineer would be automatically considered crazy if they suggested an architecture that wasn't built on a central RDBMS.
So you have to weigh it against the other cargo-cult. How many startups along the way have failed due the inability to scale horizontally?
How many have failed due to too much cost and complexity associated with re-engineering an architecture in which the assumption of fully ACID transactions permeates the entire codebase? (While the phone is ringing off the hook because production systems are falling over under load.)