Knowing what works is great. You can continue building on previous success. Equally as important is to recognize where you can improve. While it’s easier (and more fun) to focus on the positive, acknowledging where you can make adjustments will improve your products and services. With email marketing software, it becomes easy to gather such data by tracking conversion and click-through rates.
Once you've tested the entire roster of emails listed above, you'll see that subscribers respond to some emails more than others. Don't be surprised if they're not just looking out for discounts. After all, email marketing is really about building a long term relationship with your subscribers. That kind of relationship-building requires more planning and variety. In return, you'll get better brand recall and customer loyalty.