Sometimes I stumble across answers to questions I didn’t know I had. This blog post about why speedometers have speeds going up to 160MPH is a recent example. The majority of folks don’t have vehicles capable of achieving anywhere near that speed, and even if they do they’re unlikely to ever actually drive that fast (sorry, Sinclair). …so why have an instrument with a top-end measurement that’s so far outside of likely - or even possible - operating parameters? (Quick side note: Yes, I fully recognize that Teslas are all the rage and that BMWs are the sort of “Honda Civics of the Bay Area”… but I’m talking about actual cars that real people own in the Real World, folks, so bear with me here…)
For those too lazy to click through the tl;dr is - in a word - aesthetics. “These go to 160” is a design decision that ensures that speeds within the range of the typical operating speed of the car are in the easiest place to read: at the top.
Huh. Nifty.
This got me searching for other similar examples. Thermostats might be the closest thing I can think of. A typical thermostat has a range from 50F to 90F. Those temperatures are respectively colder/hotter than you’re likely to want to keep your home, but using these bookend temperatures places the common operating range (within a few degrees of 70) at the top.
I also went back through some old igotws looking for this lil guy - an example of changing the upper/lower bound “bookends” in order to remove UX occlusion of the interesting data points.
It’s actually easier for me to think of counterexamples - places where this design approach doesn’t work or is actively detrimental to the user experience. Like…think about fuel gauges. Suppose instead of being on a continuous scale from Empty to Full they went from 0 to 100 gallons. (Your gas tank likely holds something on the order of 15-16 gallons.) How furious would you be if every time you filled up your tank the gauge told you that you were at “16%”?
Anyhow. Happy Learning inDay, folks!