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The mental model mismatch

Humans think in terms of mental models. In IT it is our responsibility to help them form accurate models as well as deal with inaccurate models that exist.

Humans use mental models of how things work to fill in context. If we are not given the model, we make one up. This made-up model may be unrelated to how things actually work, but if it is sufficient for us to get our job done then that's "good enough". I think this is evolutionary: we didn't know why the sun rose and fell, but we made up a model that included a god riding across the sky... a model that was good enough to deal with the fact that "night" and "day" alternate.

As sysadmins we often skip the step of helping users create that model then have an up-hill battle as we deal with users that have created their own, inaccurate, model. We see users do things that seem insane but are actually completely appropriate for the mental model they have created.

I saw a user plug two ports of his desktop ethernet switch into wall jacks so that he could get twice as much network speed. In his model, network bandwidth like electricity in a parallel circuit and this seemed like a reasonable way to get more bandwidth. Instead he crashed the network because he created an ethernet loop (this was before loop detection/prevention mechanisms were common).

When possible we must give users an accurate mental model. However, those opportunities are rare.

When we answer technical support questions we must be on the look-out for a user with a mental model that is inaccurate. It may have served them in the past but is insufficient for their current situation.

Years ago I was at a company that was changing VPN software. Announcement after announcement went out telling people that if they used the VPN they had to stop by the helpdesk to be switched to the new software. They were warned that the old VPN would stop working on a specific date. On that date, the helpdesk was flooded with users that couldn't understand why they couldn't connect to work. "Have you seen the emails about the old VPN being replaced?" "Sure, but I don't use a VPN."

In their mental model they didn't. The icon was called "Network Connect". Why would they pay attention to an email about "the VPN"? They never saw an icon or menu with the phrase "VPN" in it.

Who's fault was this situation? Hint: The user can't be blamed for not knowing that "Network Connect" is a VPN.

"Network Connect" was the icon they clicked that connected their laptop to the work network so they could access "work things." Their mental model was more like an on-off switch. When the switch is "on", web sites inside the company work. When it is "off", those sites don't work. The fact that they're still using the same web browser and other apps helped create this inaccurate model. The switch is turned on and things magically work; turn it off and things magically didn't. Their model didn't include encrypted packets. It didn't need to. In fact, during this we learned that many users were connecting to the VPN even when they were in the building. This, again, makes sense if "Network Connect" was an on switch that made internal services accessible.

This mental model mismatch contributes to a lot of the ills of corporate IT. In situations where people don't know I'm a sysadmin I often hear complaints about their company's IT department. Often I hear about the IT department doing bizarre things "just to make it more difficult to work here". It is a sad state of things that people feel that IT departments would do that. However with incorrect mental models so commonplace it makes total sense. Why would the IT department hide our websites unless a magic on-switch is flipped? What's to stop bad people from just having an on-switch installed on their laptops too? Now if enabling the VPN made their web browser display a "ah! this is an internal site! please wait while we connect through the VPN tunnel" message every time they accessed an internal website then the mental model would include some kind of tunnel analogy. Of course, that would be silly. Plus, the great thing about VPNs is that they are transparent to the applications.

The next time you send email to users consider, "What am I doing to create an accurate mental model?" and "What mental model might they have that I should play to?" When helping a confused user consider pausing to consider, "What is their mental model?" and either work within it or work to help create a new, more accurate, mental model.

Posted by Tom Limoncelli in Professionalism

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2 Comments | Leave a comment

More accurately, their knowledge base on the subject just isn't there and is very limited. In addition, their frame of reference is different. The users haven't been informed that is the VPN that they are using.

Your "silly" point point about displaying messages to the user isn't so silly, to some:

(I picked this up via )

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