Notifications play a crucial role in enhancing collaboration within software products by engaging users and encouraging them to return to the platform. Effective notification systems, which include comments, mentions, and replies, can significantly impact user interaction and retention rates. These systems must carefully consider factors such as batching, prioritization, and recipient scope to avoid overwhelming users while ensuring they receive important updates. Batching combines multiple notifications into a single alert, prioritization distinguishes high-importance notifications like mentions, and recipient scope determines who gets notified based on interactions. By maintaining a balanced notification system, products can close engagement loops, ensuring users find value in collaboration features. Tools like Knock offer APIs to streamline the development of such notification systems, enabling businesses to quickly implement efficient collaboration features without extensive in-house development.