Jake Knapp writes that you can build better products by designing the marketing first:

Okay, let’s pretend I grab you and stuff you in a DeLorean. We time travel a few weeks into the future. Your latest project has just been released.

Imagine you can see the launch page. It has a nice simple headline explaining the appeal of your product, with a couple of secondary call-outs. You print the screen, hop back in the DeLorean, and return to the present.

With this glimpse of the future in hand, your team will be better at focusing on the core of the product. If it’s on the launch page, double down! If it isn’t, think hard before spending any time on it.

That reminds me of a similar technique used by Amazon called “working backwards”. It’s outlined in this Quora thread:

For new initiatives a product manager typically starts by writing an internal press release announcing the finished product. The target audience for the press release is the new/updated product’s customers, which can be retail customers or internal users of a tool or technology. Internal press releases are centered around the customer problem, how current solutions (internal or external) fail, and how the new product will blow away existing solutions.

Once the project moves into development, the press release can be used as a touchstone; a guiding light. The product team can ask themselves, “Are we building what is in the press release?” If they find they’re spending time building things that aren’t in the press release (overbuilding), they need to ask themselves why.

These are both great techniques to prevent scope creep and ensure that you’re building products that have clear user benefits.