Scale complexity arises when a subdomain’s overall complexity comes less from difficult business rules than from high volume, throughput, failure exposure, operational demands, and severe failure consequences. Larger scale requires greater robustness, increasing maintenance costs. section 10.2.2
Two booking systems
A booking system processing tens of thousands of orders daily has higher scale complexity than one processing tens of orders daily. Minimal downtime may be acceptable for the smaller system, while the larger system must tolerate more failure and limit more serious consequences. section 10.2.2
Use annotations to indicate operational complexity when comparing subdomains and identifying where scale increases robustness needs. section 10.2.2
