Bounce rate is one of the most essential matrix to know whether your mass email marketing is being successful or not. They have an inverse relation with one other, Lower the bounce rate, higher the success rate in bulk email marketing.
If you are spending too much time and money to get new customers, then STOP RIGHT THERE and focus more on your existing customers. Every successful business has customers’ list that is acquired obviously over a period of time. But that isn’t permanent… All businesses lose their customers now or then, therefore it’s very necessary to maintain the existing customers.