Fully backed feature/thorough-experience vs half backed feature/functionality.
Fully backed feature allows us to tell many stories around it where as half backed feature/functionality will have limited/one story telling.
Great products have features which are used more often and beyond the initial use-case. For instance.
The basic ability/use-case is to use the chat app to exchange simple messages instantaneously. The basic use-case philosophy was users will chat when they need/require to.
But by giving users ability to show custom status messages this have changed the basic use-case. Not only people can chat but can decide not to chat if they see the status as "busy".
Users have taken the use-case to total different level by using custom status messages, For instance a custom status message sets the mood for the conversation. The use-case have now changed to not just to chat anything but also shows what mood the other user is in.
The basic is to believe how a product can evolve over time and learn how users can transform a product from its initial inception. Ability not to see this will cost dearly.