First of all the assessment of quality is down to you as its your list... What factors are important? What is your aim? Figure out what is that you want to achieve and then assess how well your list performs against your benchmark... As an example:
- How many people open your email messages? In otherwords what is the % of engaged users... If its low why is that? Perhaps your messages are boring, offer no value... What is the value that you are aiming for i.e. does 70% open rate meets your quality criteria?
- How many people buy products from your list? What is your aim here.. i.e. Does 5% buy into recommendations? Does that meet your quality expectations? If not then ask yourself how can you improve that....
- Also consider cleaning up your list i.e. Remove people whom never respond from your list in order to lower your operating costs... and in the same token improving how you target opt-ins e.g. use of ads which targets interests, keywords etc
As you can see ask yourself some basic questions and then assess the actual situation versus your ideal situation which you should use as a quality benchmark... Use that to take corrective action....
At the end of the day an unresponsive list is worthless no matter how many people are on it... So it is always worthwhile to examine its performance and to improve on it..
Hope that helps...
