There are some cases when email newsletter may do harm. Main one is sending SPAM newsletters. When users did not give initial agreement to receive newsletters, and you send non-authorized newsletter on behalf of your company using corporate style, it is a SPAM. It may either attract attention to your proposition or antagonize them forever.
Potential interest as for you newsletter may be, if your mailing base is collected at topic resources. Ideal mailing base consists of your previous or repeat clients.
You must understand that email marketing requires professionalism. There are no trifles here, high effectiveness can be achieved only by trial and error. After gaining some experience you will understand that newsletters give high ROI.
Let’s consider some other aspects. Newsletter formatting is very important. It must be professional and shouldn’t contain any extra repulsive graphics. We recommend you to use text format for your newsletter.
Also your clients may be repulsed by very frequent newsletters. Don’t be over-diligent. It is enough to send newsletter once a week. Any newsletter must have useful and topical content.
So, email newsletters may do harm, but it happens only in the case of non-professional approach, and when you don’t pay enough attention to small things.