Let's say I needed a `leftpad` lib from npm - it would be imported and re-exported from `./lib/leftpad.js` and my codebase would import leftpad from `./lib`, not by its npm package name. If / when a better (faster, more secure, whatever) lib named `padleft` appears I would just import the other one in `./lib/leftpad.js` and be done. If it had incompatible API (say, reversed order of arguments) I would wrap it in a function that accepts the original order and calls padleft with the arguments reversed so I wouldn't have to refactor imports and calls in multiple places across the project.