What frameworks, besides user personas, can help us understand our customers so we can improve messaging?

I love the JTBD (Jobs to be Done) framework for improving messaging.

The JTBD framework helps define the high-level tasks your users are trying to accomplish using your product and how they evaluate success. When you deeply understand what users are "hiring" your product to accomplish, you can shift your messaging from focusing on features to emphasizing the value to the user.The classic quote on this style of thinking is from HBS Professor Theodore Levitt: “People don’t want to buy a quarter-inch drill. They want a quarter-inch hole!”

To stretch this example further, consider the high-level tasks drill buyers are looking to accomplish with the hole (e.g., hanging a picture, building furniture, fixing a roof, etc.) and the various ways they measure success (e.g., achieving the task cheaply, easily, and with precision). As a drill manufacturer developing messaging, rather than marketing the technical components (e.g., "It's made from x material"), it's more effective to use language that addresses the user's JTBD and success metrics (i.e., the drill is purpose-built as the easiest, most precise way to accomplish household tasks, at a competitive price).

The beauty of JTBD is that it not only guides your messaging but can also inform the product roadmap. For example, going back to the drill, what features can we add to make it more precise? Maybe a leveler or a laser guide to show where you're drilling?

For more about JTBD and how to conduct JTBD interviews, I highly recommend "The Jobs To Be Done Playbook" by Jim Kalbach.