Depending on your business model, getting people to spend/donate/deposit their money is likely what it's all about. Direct Mail (DM) is Database driven. As such it is a huge revenue driver. It's one of the few marketing disciplines that can say "Give me a dollar, I'll give you back a buck fifty."
Most people have a very low opinion of Direct Mail - the derogatory term "junk mail" is proof of that (which would also explain why up to half of it winds up thrown away ... unopened). But the volume of "junk mail" into the consumer's mail box shows little sign of slowing down. According to Mail Monitor, a record 6 billion credit card offers were received by US households during 2005 alone. An offer is what the reader gets when he responds to your mailing. To be successful, a direct-mail package should sell the offer, not the product itself.
For example, if I mail a letter describing a new mainframe computer, my letter is not going to do the whole job of convincing people to buy my computer. But the letter is capable of swaying some people to at least show interest by requesting a free brochure about the computer.
Make sure you have a well-thought-out offer in every mailing. If you think the offer and the way
you describe it are unimportant, you are wrong.