This EventEmitter is missing a method to remove listeners: 1) Without a way to remove event listeners, they accumulate indefinitely, 2) This creates memory leaks as objects referenced by listeners can't be garbage collected, 3) A proper implementation needs an 'off' or 'removeListener' method to detach listeners when they're no longer needed, 4) Event emitter patterns are a common source of memory leaks in JavaScript applications, 5) Listeners often create closures that capture references to other objects, compounding the leak, 6) Node.js's EventEmitter and browser event systems include listener removal methods for this reason, 7) The ability to detach listeners is essential for proper object lifecycle management, 8) This demonstrates how incomplete implementations of common patterns can lead to memory issues.