AWS Netflix consumes enough resources that if they spike 40-50% everyone is screwed. The software required to run the cloud like AWS is orders of magnitude more complex then what avg project would need and results in major screwups. Both major AWS outages were due control plane issues second case was result of massive Netflix migration that triggered throttles for everyone in affected AZs. The throttles in the first place were put in due to the major outage that lasted for many hours.