The results of an email prospecting campaign may seem quite low. However, this is do to the nature of mass emailing. The most important thing to look at when you send bulk email is the click rate. On average, a mass email marketing campaign will deliver an open-click through rate of .1%-1%.
This number seems low, yet you must remember the type of emailing you are doing and the ROI. Look at the costs associated with Google Adwords pertaining to clicks. You may spend a hundred dollars for 30-40 clicks. Yet, with mass emailing you can get a couple thousand for roughly the same price.
Email prospecting is a numbers game. You want to be sending hundreds of thousands or millions of emails at least three times a month. Similar to advertising in other channels, the target audience needs to see the email at least three times in order to act on the email.
If you play your cards right, you will have a great ROI with email prospecting. Add another advertising tool to your belt and start to draw in new business.