The singleton design pattern, while simple, is often misused. Bartłomiej encountered numerous incorrectly implemented singletons in inherited code. One example attempts singleton creation within the constructor, failing to guarantee a single instance. Multiple instances can be created, replacing the previous one. The DoSomething method attempts to identify the correct instance, silently failing otherwise. This implementation does not achieve even the basic functionality of a singleton. It essentially functions as a flawed global variable. The code's design is fundamentally flawed. The presented example highlights common singleton implementation mistakes. The singleton pattern's simplicity often leads to incorrect implementations.