Most microservices migrations fail because teams jump straight from a messy monolith to a distributed system without understanding domain boundaries. The author, having seen two failed migrations and one success, argues for a slower, more deliberate path: first modularizing the monolith using Domain-Driven Design to identify bounded contexts, then extracting services selectively.

The successful pattern is monolith → modular monolith → selective microservices extraction. Teams should spend 3-6 months restructuring code into domain modules with explicit interfaces, enforcing boundaries with tooling, and proving they can maintain a well-structured codebase before adding network complexity.

Extraction uses the Strangler Fig pattern with an API gateway routing traffic. Start with high-change modules like authentication, using Anti-Corruption Layers to translate legacy data models. Feature flags and shadow traffic enable safe rollouts. The author notes that for many teams, a modular monolith is a valid endpoint, not just a waypoint.