When is the Singleton pattern most appropriate in JavaScript applications?
The Singleton pattern is most appropriate when exactly one instance is needed and must be accessible from a well-known access point: 1) It's suitable for coordinating actions across the system, 2) It's useful for resources that are expensive to create or must be shared, 3) It's appropriate for managing configuration that must be consistent, 4) It fits cases where having multiple instances would cause incorrect behavior, 5) It should be used sparingly as it creates global state which can complicate testing, 6) Common examples include logging services, configuration managers, and connection pools.