Michael Brenner titled a recent blog post Personas Are Great (Except When They Suck). True. But now compare two situations: In one case, the personas suck and everybody knows it. And, in the other, they suck, but most people think they’re just great. The first case is unfortunate. The second? It’s actually dangerous.

So, how can you spot a persona that sucks, even if it looks great?

Here are three clues:

Clue #1: Lots of collated opinions, but no new primary research

Personas suck when they are constructed without primary research at their core.

A recent ITSMA survey found that of all the investments made in personas in 2014 by companies in North America, only 15% involved primary research. To flip that around, 85% of personas were built off of something else: consensus views, or “common sense” or perhaps a projection of operational data.

Why is that a problem? Personas can help organizations be more empathetic. But, without new primary research at their core, personas are more likely to be simply a mirror for the organization’s projected biases. That’s not going to help the organization innovate, get closer to its customers or speak in a language that engages and connects. If we conduct no new research, and employ instead only a collection of assumptions, we reinforce an internal worldview. That worldview is constantly at risk of drifting farther and farther from the consumer’s reality. No need for personas to add to the problem.

Clue #2: Form that doesn’t follow function

Persona skeptics grumble loudly about references to irrelevant, extraneous narrative details included in personas: “Who cares whether she has a cat?” “We’re not selling cars…what difference does it make what color of car she drives?”

Depending on context, the skeptics might be right or wrong. For sure, persona advocates owe the skeptics a justification for the “cat” or the “red car” other than the convention of including personal details. The justification is this: Form follows function.

“Form” in this context means the totality of all elements of the persona working together as a meaning system. And, in order for form to follow function, two conditions must be met. First, if a persona is presented as part of a set of personas, and a detail is included about one persona, then that detail should have counterparts in the other personas to provide a structured framework of comparisons. For instance, the “red car” might be a vivid way to communicate differences in the desire for self-expression as long as there is a counterpart to that observation in the other personas. Second, that framework of comparisons needs to be relevant to the “function”—the application of the persona insight to the design of something. Does the “red car” reference help web content developers properly appreciate the customer meaning of “personalization” as a topic in the buyer journey for a piece of software? In that case, maybe the “red car” totally belongs. The “cat,” on the other hand, might be complete rubbish. Form must follow function.

Clue #3: Too much reduction, not enough substance

Creativity is a defining characteristic of effective communications. And, when it comes to creative work—like customer experience design, brand building, content marketing and product design—marketers and CX professionals are best equipped to do great work when they can draw on the full capacity of their imagination—not just the deductive reasoning portion of their mind.

For this reason, the time-honored business axiom KISS—or keep it simple, stupid—can be a stupid axiom when it comes to building personas. Personas with nicknames like “Shopper Sally,” personas that stop at cataloging a set of demographic observations without drawing them into a story, and personas that are built around a label and a stack of bullet points—these are all aimed at the deductive reasoning, rational side of the mind. From the standpoint of firing the imagination, they could be so much better.

Good personas incorporate storytelling elements that appeal to our sense of empathy and identification with other human beings. Great personas encode deep customer insights that speak to our intuition. They activate the side of our thinking that is hard wired to form snap judgments based on a facial expression. They speak to the side of us that cannot resist reading meaning into a complex pattern of associations. And when they do, they produce a sense of clarity about what to do and why that can be tremendously helpful in designing experiences that resonate with customers. Reductive personas that flatten the mental model of the customer out to a one-dimensional cartoon are not going to stimulate that kind of creativity.

So there you have them: three quality tests to check whether the personas you’re using are great, unfortunate or just plain dangerous.

What do you think? Do these tests give you a new way to look at the personas you’re using now?