A persona is a marketing tool that helps to better understand one's own target group. The persona is described in detail so that everyone in the company has the same understanding of the persona.
The advantage of this is that the requirements, needs, and desires of the target group can already be thoroughly examined during the planning of the customer journey. This saves laborious adjustments to the content and alignment afterwards.
A buyer persona functions as an accessible representation of the target group and should be as realistic as possible. Planned marketing measures can thus be tested in advance on the persona and any weaknesses can be eliminated.