Historically, it has been difficult to measure the effectiveness of marketing campaigns because target markets cannot be adequately defined. Email marketing carries the benefit of allowing marketers to identify returns on investment and measure and improve efficiency.[citation needed] Email marketing allows marketers to see feedback from users in real time, and to monitor how effective their campaign is in achieving market penetration, revealing a communication channel's scope. At the same time, however, it also means that the more personal nature of certain advertising methods, such as television advertisements, cannot be captured.
If links and looks are set, begin interacting with the page. Abandon it, adjust the window size, convert. Are error messages appearing when they’re supposed to (if, for example, you don’t input all the form’s required info)? Is your CTA button working? If you abandon the page, are you retargeted with ads? When you resize the window, does your landing page respond accordingly?