The article mentioned below is well worth a read! For me the key point is that your content (if you are doing it right) should be helping customers to decide whether you are the right fit for them and what they want to achieve and serves to validate (or not!) what they have already heard about you.

Even if they get a word of mouth recommendation, the great majority of people will take to Google to find out more. It's increasingly vital that your website, and the content on it reinforces the story that your promoters and advocates  are telling. 

It's equally important that your content serves to help the people you won't be able to help make that decision for themselves so that you can spend your time on the people you can....