Premature Celebration

Definitions

Feeling or signaling victory before the system has truly proved itself. In engineering slang, premature celebration is a known failure mode around deploys, benchmark wins, and partial green dashboards.
In plain English: Celebrating success before it has actually been proven.
Example: "The team caught itself in premature celebration when the first five minutes looked clean, then remembered the real traffic spike would not arrive until the top of the hour."