Consider the following two user interfaces…

2019 Dodge Grand Caravan:

2019 Subaru WRX:

The Caravan I just employed as an Enterprise rental from Stamford to Columbus.  Its fold-down seats are kind of awesome, allowing it to transform effortlessly from minivan to cargo van.  It proved perfect for transporting a mix of precious belongings and my feline companions, the latter of which I wanted sharing a climate controlled space with me.

The WRX I enjoy as my everyday car.  I acquired it last fall when, heartbreakingly, I lost my beloved Audi S4 in a flood.  The WRX remains one of a vanishingly small number of cars one can acquire in the US market that offer both AWD and a fully manual transmission.

But these are not the features under consideration today.

Imagine that you find yourself on the road in your rented Caravan just shy of Columbus and suddenly in an epic downpour.  The 18-wheeler in front of you brakes hard and engages its hazard lights.  You likewise brake hard and reach to engage your own hazard lights when…  fuck, where the hell is the button?  You look up and in your mirrors see another 18-wheeler barreling toward you, oblivious to the emergent conditions.  In desperation you slam on the gas and veer rightward into the breakdown lane.  The following 18-wheeler belatedly realizes the crisis it has created and veers leftward.  The two of you collaborate to thread the needle, catastrophe avoided by the narrowest of margins.

Suppose you find yourself in such a moment while driving the WRX and wish to engage your hazard lights.  Your right hand’s fingers relax, your triceps contracts, your hand finishes opening, and your palm mashes the giant red button that inhabits a space all its own.  DONE.  Crisis (hopefully) averted.

Consider, now, the same situation, but you are piloting instead the Caravan, as I was.  You look for the hazard light button in the conventional region but it is nowhere to be found.  It is hiding.  Its red matches the color that indicates heat for the climate control system.  Its size measures less than half of the adjacent buttons of purpose far less desperate.  Its location is well below the plane of where one’s eyes naturally travel and requires that your arm first drop and then thrust and furthermore poke with a single finger.

Which UX would you prefer in an emergency while piloting an unfamiliar vehicle?

How many lives have the UX designers of Dodge cost with the careless placement of a single button?

Your choices as an engineer can yield weighty consequences even if you never get to see them directly.  Have empathy for both the novice and the expert, the casual user and the crisis-beset operator…  Your efforts to mind the details may make all the difference.