To maximize the value of a successful list, the size of the list becomes an important decision in the selection criteria. In testing lists for maximum value it is much better to select larger lists so they can be provide a good return quickly if they perform well.
For example, at first select a sample of 5,000 names from a large list, if this sample produces consistent good results, then test and additional 10,000 names from the list. If the increased sample continues to provide effective results, then utilize the entire list.
The value is to maximize the opportunity of a list that test well and exploit it to its full potential as quickly as possible.