An email without a solid call to action is just another email. In your electronic marketing efforts, you can nail the subject line and get your recipient to open the email, have an amazing story that perfectly shines a light on your mission, but if you neglect your call to action, you’ve wasted your efforts.
Knowing your audience is a good start to crafting your ask. Respect the fact that your reader likely has multiple “asks” in their inbox and yours is just another option. Don’t waste their time, or yours, giving details that don’t add to the specific intent of your email. If the email has been crafted to ask for support of a specific event, give the details of that event and get to the ask.