# The failover test that stopped the wrong node

Recent technical reports highlight critical failures in software testing and deployment. One case reveals a concurrency test for Effect.all that passed despite being sequential, failing to detect production bugs because operations did not overlap. Similarly, Squirix 0.1.0-preview.8 shipped with a failover feature that was fully tested and documented but remained inactive in the production host. Both instances demonstrate how green CI and passing tests can mask significant functional gaps in live environments.