Well before it would hide the images, so there were a lot of people who read the emails, but the ping to the marketers server was blocked by default. Now the de

Well before it would hide the images, so there were a lot of people who read the emails, but the ping to the marketers server was blocked by default. Now the default is to show email images, which tells the marketer that you opened the email. So, for the few people who clicked "show images in this email" before the change, the marketers lose the richer metrics they were getting. But in return they gain slightly less granular metrics for a lot more people.