Designed for Use, 2nd Edition

Consider the Cost

Every new feature has both a value and a cost. To properly evaluate the impact a new feature will have, it’s important to consider both aspects.

A feature’s value is usually quite obvious—namely, what it allows your users to do.

But the cost of adding a new feature to your product might not be readily apparent: the additional complexity might take a toll on people who aren’t interested in using the feature. Adding a new feature to your product prevents you from working on other things, and having it in your product might slow down future progress because you have to maintain yet another feature. A feature that relies on systems you can’t control, or that is error-prone for other reasons, might lead to rising costs in user support. ...