Buyer personas can be created through research, surveys, and interviews — all with a mix of customers, prospects, and those outside your contacts database who might align with your target audience.
But like all data, even information you gather on your audience (your personas) can go out of date. After all, business models change, companies merge or shift direction, and your audience can (and likely will) evolve. In your professional opinion, how often should you audit and even update your buyer personas?
Personas should change when the business or industry have involved, the decision making and thought process of the customers could change as well. Thus reviewing the buyer personas from that perspective might be more effective, looking at search volume from the internet might give you an idea what is trending and how those trends changes the consumer behaviour
In my opinion these personas should be re-evaulated yearly for updates; larger changes should be informed by brand research, which in our business will likely be completed in depth every 2 years.