State Machine Implementation Framework

State machines fail when they're implemented as unconstrained if-else chains that allow any state to transition to any other state depending on how the conditions evaluate. Without explicit transition definitions, a bug can move an order from "completed" back to "pending," or a payment from "failed" to "processing" — invalid state sequences that produce corrupted data. Explicit state machines define valid transitions, reject invalid ones, and make the complete business logic of an entity's lifecycle visible in one place.

The State Machine Implementation Framework defines the complete transition table, enforces it, fires side effects on transitions, and serializes/deserializes state for persistence.