A few weeks ago I wrote abut the single box theory of software design. I have another one I’d like to add: the product box theory of marketing.

Here’s how I believe each customer’s mind works: I need to do “x” so I need to go to this service to do it. I need to share files across computers so I need to put them in Dropbox. I need to exercise so I will go over to 24 Hour Fitness. I need to buy a book so I will go to Amazon.com. I need to buy soap so I will go to Target.

As humans we like to sort and categorize, we like to put things in little boxes. We know when we need to do “blah” we can go to that little box to get it done.

If your product doesn’t fit into a box then don’t ship until it does. And if your product doesn’t satisfy the entire box, don’t ship either.

We almost learned this the hard way. When developing powerOne calculator we realized that the customer says, “I need to do a calculation so I use powerOne.” But early on we considered leaving off the general-purpose calculator. It is a real pain to develop and maintain and the iPhone had one bundled. But after a couple of customer interviews it became clear quickly that the calculator needed to be there. The customer didn’t want to say when I need to calculate this I need powerOne but when I need to calculate this other thing I need the iPhone calculator. No, the customer wants to say I need to calculate and then grab powerOne.

This box is critical for success. Without it the customer will never really latch on to using your product or service.