If your emails aren’t getting engagement, chances are they don’t land in your subscribers’ inboxes. One of the reasons could be a high spam complaint rate, which causes your messages to go to the junk folder or get blocked.
But as a legitimate email sender, why would you be getting spam complaints? It could be that you’ve purchased a list of contacts and they’ve never heard of you. Also, certain elements in your emails may lead people to hit the spam button, even if they subscribed to your list.