> which you know a priori and therefore have no need to go spelunking. Except when you're working on a codebase that's new to you, and you're trying to naviga

> which you know a priori and therefore have no need to go spelunking. Except when you're working on a codebase that's new to you, and you're trying to navigate it to make a change somewhere, so you don't have a priori knowledge about what implements which interface.