Getting to know your users (and different kinds of users) is important when designing products that affect them. Personas are a set of tools that document a user’s frustrations and core needs that can be shared with developers, management, and stakeholders.
Personas can be used to backup design by asking “What would our users think. It’s really important to get our heads out of thinking about Java beans and XML data and focus on what really matters. This user centered design philosophy allows you associate what you’re building with an actual human being (or a fictitious one). The point is to think about your users and designing personas are an effective tool for this.
One of our client’s help desk managers saw a set of personas in a developer’s office and asked for copies so they could better understand the different kinds of problems they encounter with different segments of users. In our experience, if personas are evangelized correctly, they can make a huge difference in an organizations perspective of users.