I keep emphasizing on the need for high-value content. Value to the recipient, that is.
Each communication is a means of cementing a relationship or creating/ acquiring an additional one. Over tens or even hundreds of newsletter mailings, you create/ shape your audience profile. As you add topics, probe depths or flirt with boundaries, your audience profile ebbs and flows and mirrors your current content profile.
This is more complex than it sounds, even! Let us say someone “opted-in” to receive your newsletter months ago on the premise that he will get weekly educative information on personal finance strategies. Now, as your newsletter becomes richer (broader in scope) in content and starts covering stock markets in greater depth, has more coverage on real-estate market or bullion trading two things will happen. Your could add new readership, for sure. But, you may even lose some of your core readership who joined your fold to get sound advice with how to manage their small savings, for example.
Each content area potentially is a micromarket. It is a content play for attention in each of those micromarkets. Your attention paid to each micromarket should reflect a conscious decision to influence these markets. If you are allowing shifting audience priorities to dictate your content, there is nothing wrong with that. But, let that be your choice. As with any choice you make, you live with the consequences and compromises.
As content tag shows up as a cloud of words in my blog, if only we could capture the expectations of our audience as tags! Over a period of shifting timelines, this will be instructive to see how that changes.