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 are 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.
If the benefits listed don’t sound very interesting or exciting to customers, then perhaps they’re not (and shouldn’t be built). Instead, the product manager should keep iterating on the press release until they’ve come up with benefits that actually sound like benefits. Iterating on a press release is a lot less expensive than iterating on the product itself (and quicker!).