One of the reasons churches get poor results in their direct mail is because they don't track their results.
Here's the truth: if you aren't tracking your results, you have no idea if your direct mail is working or not.
Butts in the seats is not the only way to see if your direct mail is working. While I would agree that someone attending your church is the end result we want, there are other factors involved.
1. Someone could get your direct mail and go to a confusing website and not attend
2. Someone could get your direct mail and see no website or other important piece of information
3. Someone could get your postcard, but because it gets there late your results are limited.
These are just a few reasons, but without a tracking system you'll never know what the problem is.
That's why you MUST have a tracking system for each direct mail piece you do.