Buyer personas are built on research, not guesswork
In order to truly see things from the buyer’s context and perspective, personas can’t be developed based solely on the views and opinions of the sales and marketing teams. Instead, they are based on real data obtained from independent industry research, surveys, and most importantly a substantial compilation of one-on-one qualitative interviews. While your business development staff may know a lot about your buyers, the insights that personas highlight can only be obtained through conversations with actual buyers.
For the interviews, it’s best for them to be conducted by a third party to ensure objectivity and precision. You should include a diverse mix, such as long-term and new clients, lapsed or former clients, and prospects that you’ve not been able to do business with. You’ll want to make sure you have a sample of several interviews for each “bucket” of buyer types that are also diverse in your coverage of specific markets and/or service lines. The point is, you want personas to be accurate representations of your buyers and not skewed based on the unique views and perspectives of any one interviewee.