That one new feature you added? That sparkly, Techcrunchable, awesome feature? What did it cost your user? If the result of your work consumes someone’s cognitive resources, they can’t use those resources for other things that truly, deeply matter. This is NOT about consuming their time and attention while they’re using your app. This is about draining their ability for logical thinking, problem-solving, and willpower after the clicking/swiping/gesturing is done.

Of course it’s not implicitly bad if our work burns a user’s cog resources.Your app might be the one place your user wants to spend those resources. But knowing that interacting with our product comes at a precious cost, maybe we’ll make different choices.

—Kathy Sierra is writing again at Serious Pony, which is just wonderful. This post on the designer’s responsibility helping our users manage their cognitive load is absolutely required reading.