Creating great emails takes time. But, a lot of great emails go unread.
According to Convince and Convert, 35% of email users will decide to open an email based on the subject line alone. In addition, Copyblogger states, 8 out of 10 people will read your subject line, but only 2 out the 10 will actually click on it.
That means that much of the time and resources you spent on crafting subject lines is being wasted.