There are a bunch of bills that I pay every month where I want to enter exactly the same description. Without this feature, I have to guess whether to enter, for example, "Fort Worth Water Dept" or "Water Dept" or "Water Utility". I don't want to memorize the exact wording for 15 or so regular items; rather, I desire Checkbook to prompt me with what I entered the prior month.
Checkbook DOES have the nice feature of prompting me once I enter a few characters, but as the example above shows, I don't always remember what the first few characters are.