Not all fundraising offers are made for direct mail. Some causes just don’t lend themselves to direct mail. This can be because your audience is so small you can’t get the economies of scale necessary to make direct mail a cost effective proposition.
And some offers won’t work in direct mail because they’re uncomfortable. We’ve seen this in recent years with rape crisis centers, human trafficking and domestic abuse shelters. These organizations are all doing vital work to help extremely vulnerable populations. But no one wants to read about the terrible situations that take place every day that require organizations like this to exist. And if people don’t want to open or read your direct mail because it makes them uncomfortable, then you probably shouldn’t spend the money to produce and mail it.