It's lingo from Amazon's corporate culture. This article explains it well: https://aws.amazon.com/executive-insights/content/how-amazon-defines-and-operationali

It's lingo from Amazon's corporate culture. This article explains it well: https://aws.amazon.com/executive-insights/content/how-amazon-defines-and-operationalizes-a-day-1-culture https://aws.amazon.com/executive-insights/content/how-amazon... > Day 2 is stasis. Followed by irrelevance. Followed by excruciating, painful decline. Followed by death. And that is why it is always Day 1.