The difficulty in responding to these questions is due in part to the nature of the creative process. Another part of the difficulty is the result of assessing creative and email against a set of loosely defined criteria. Judgments and hypotheses on the layout and design are typically driven by a combination of instinct, subjective aesthetics, personal preferences, some best-practice chestnuts, and maybe some insight into historical response trends. But in the absence of a definable set of criteria with which to evaluate email creative, everyone has his or her own view and preference, and rendering a solid assessment and action plan can be challenging.

We often advise clients on "creative optimization," which is really a methodology for deconstructing email and developing evaluative assessments for maximizing performance. Optimization, among other benefits, establishes clear criteria, provides an analytical framework, and keeps feedback focused on key elements. In many ways, the process is similar to the type of critical analysis applied in the fine arts, where, in order to infuse objectivity and "science" into what is primarily an aesthetic endeavor, certain technical and structural elements are defined and isolated for analysis.

All creative optimization projects (whether for landing page, Web site, conversion, media, or search) begin with establishing priorities -- starting with foundational elements and working up. This has also been referred to as the optimization hierarchy. Here are some of the most desirable elements you'll want to achieve in your email optimization hierarchy, in ascending order of nuance.

Accessibility: Is the layout designed to meet delivery and rendering best-practices? Ensuring your email gets into the recipient's inbox is primary. Best practices and channel considerations are a useful guide, and there are a few definitive rules you can't break. But don't be guided by best practices alone. The nature of the channel is such that best practices are changing all the time. And what is best practice for one audience may not be for another audience, or another offer.

Usability: Is the layout aligned with the way in which recipients are expected to engage with the message? What is the logical path of the eye? For most messages, this means scanability. Do the calls-to-action fall quickly within the eye path, and are they salient?

Efficiency: Is the layout well-suited for rapid design and testing, or is it a custom one-time-use only that would require a complete redesign for subsequent uses and testing?

Appropriateness: Does the creative deliver the message, tone, and payoff for the intent of the email? Does the body header create a logical sequence from the subject line, or is it merely a reiteration? Is personalization, or lack thereof, appropriate? A broadcast, undifferentiated promotional offer, for example, might be cheapened by adding name personalization, whereas it's probably a requirement for a transactional "thank you" or welcome message.

Being Engaging: Are there interesting and unusual graphical elements that draw the eye and reader in, such as animated gifs, unique call-out treatments, or irresistible subject lines? Does it encourage the recipient to open, read, and click through?

Email creative is like marketing itself: equally art and science. Create an analytical framework, and the creativity will flow.

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