You are right that you need to know these attributes of your customers, but it is even more important to research and understand how your customers go through the buying process for what you offer. Whether it is readers deciding whether to open your post, or IT people deciding which software to buy, your buyer has certain things that trigger the need to do something, has desired outcomes they’d like to achieve, has decision criteria used to narrow options and select one, has objections that raise doubt, and has buying process steps that they go through. It is only by having this insight that you are able to market and sell what you offer successfully and at scale.
RE: Who is our customer? and why is it important.