The Akka Toolkit follows the Let it Crash model to take care of fault handling. When a subordinate Actor crashes, let it crash and do that fault handling with the help of another Actor. This means the subordinate does not need to worry how to handle that situation. The supervisor of that Actor will take care of that fault handling based on the configured supervision strategy.
This Akka's approach clearly defines who is responsible for taking care of fault handling (supervisor Actors) and who is responsible for actual business logic (Subordinate Actors). This loose coupling and the SRP (Single Responsibility Principle) approach gives us the ease of fault handling and lightweight Actors. Refer to the Supervisor strategies section for more information on this.