For a product to grow mostly by itself, what important capability should it offer users?

The most important capability a product should offer users for it to grow mostly by itself is to facilitate and incentivize user-driven growth. This capability is commonly known as virality, which means the product is inherently designed to spread among users through their interactions. For a product to grow mostly by itself, its existing users must be empowered and motivated to bring in new users, creating a self-sustaining cycle of acquisition without heavy reliance on external marketing or paid advertising. This process works by establishing a viral l....