Every time I encounter a crap circle my heart sinks. I first wrote about these contemptible “information” graphics in HBR in 2005, and since then they’ve only seemed to multiply. You know what these are — you may have even used them — though you may not have had a name for them. I aim to change that. These pernicious circles-and-arrows diagrams infest PowerPoint and other business presentations, purporting to clarify an idea while actually obscuring it.

As I wrote back then, when you find yourself about to drop a crap circle into your slide deck, stop. And the next time a presenter trots out a circle to make a point, call him on it.

Here’s the original article. I urge you to forward it to violators, and submit examples in the comments below of the worst (or best?) crap circles you’ve encountered.

The most dubious business plan can look solid — even smart — if it’s cast as a virtuous circle. “See, we invest our profits in innovation to create delightful products that customers buy — which generate profits that we invest in innovation!” Who could argue with that? Indeed, the merit of self-reinforcing systems seems so obvious that businesspeople instinctively describe their strategies as cyclical activities that magically fuel themselves. Meanwhile, audiences demand snappy-looking, easy-to-digest graphics that, almost by definition, strip away nuance. It’s no surprise, then, that business communications are lousy with circle-and-arrow diagrams that range from the dumb to the deceptive.

Though you’ve seen a million of these, you’ve probably never thought much about them. That’s because, like optical illusions, they play on your expectations and trick you into seeing something that isn’t there: If one arrow leads to the next, then of course the steps follow. But once you start examining these ubiquitous diagrams, you’ll be amazed by what you don’t see.

Consider these examples:

The circle below, from a global accounting firm’s website, is used to illustrate the company’s consulting services for owner-managed businesses. It shows the business life cycle “maturity phase” leading, inexplicably, into the “conception/ start-up phase.” This company’s clients should ask whether they really want to be guided in circles.

With the next design, a Boston-based software company helpfully illustrates the stages of its application management life cycle. Through some trick of causality, termination leads to deployment. This may be a good model from a consultancy’s standpoint — when a client’s projects end, they start again — but if you’re paying the tab, you probably want the project to actually end when it’s terminated.

The friendly-looking sunburst that follows, captured from the website of a solar energy advocacy group, shows how to create an unlimited market for your product. Here, as the supply of solar energy increases, so does the demand — in an apparently endless cycle. If these folks are right, we’re all in the wrong business.

And this one, from a Canadian enterprise-content-management company, is notable for its sleight of hand. Circles rotating in opposite directions (in which, among other oddities, “publish” gives rise to “search”) link through arrows whose origins and destinations, on close inspection, are obscure or completely hidden. Maybe the intent of this diagram is to make prospects too dizzy to ask questions.

Kudos, though, to the author of the disarmingly honest graphic below, from a U.S. safety engineers group — a refreshing bit of out-of-the-circle thinking. He seems to have had an epiphany as he created the diagram, realizing that the development of safety processes doesn’t always chase its tail — that “management review” needn’t slavishly feed into “strategy and policy” in the service of “continual improvement.”

By fighting the impulse to think in circles, he’s set an example for everyone who has uncritically accepted or, worse, actually constructed a crap circle — and that’s most of us. The next time you find yourself preparing a circle for a presentation, ask yourself if the process you’re describing really works the way you say it does. And the next time a presenter trots out a circle to make a point, find the bogus links and put him on the spot. We could all benefit from a little more linear thinking.