You Don’t Need an Interface for Everything

Ever noticed how every service in your .NET app gets its own IWhateverService interface—even when there’s only one implementation? This video argues that most of those interfaces add zero real value. Instead, reach for a delegate or abstract class when you truly need testability, pluggable behavior or multiple implementations, and stop letting outdated DI tutorials force you into needless boilerplate.

They dig into when interfaces actually make sense, how the “interface-all-the-things” habit started with Dependency Injection teachings, and even cover using delegates (3:25), overrides (4:33) and closing thoughts (6:30).

Watch on YouTube