Do your donors know exactly how awesome they are?
They might not if you thank them the way a lot of fundraisers do:
Our people and processes are the best! We've accomplished so very much. Thank you.
The Communicate! Blog has good thoughts on how not to do that, at What Nonprofit Donors Want to Hear:
...the more you portray your organization as the donor's tool for doing what they want done, the more likely your donors are to give. And to feel proud of themselves. And to give again.
When you acknowledge a donor's giving, the subject isn't your awesomeness. It's theirs. You should tell a powerful, emotional story about something great that happened because of donors. And then say...
Thank you for making this possible. It can't happen without your generosity! You are the best!
That's what donors want to hear. That's what will make them want to give repeatedly.
And sadly, it's what they rarely hear from the organizations they support.