Death by Edge Case: Why We Shouldn’t Blame Tech When Fringe Cases “Break” Our Apps

Ewuranna Smith-Quayson
5 min readDec 4, 2023
Photo by ThisisEngineering RAEng on Unsplash

Raise your hand if this unfortunate drama sounds familiar:

You’re walking your usual 10k daily steps, phone in pocket, minding your Fitbit business as your personal step count steadily ticks upwards. 10k steps come and go. Then 15k. At 20k steps (did you take up marathoning overnight?!), your phone quits counting.

Frustrated, you check the app only to see your account locked for “suspicious activity.” Rude! You appeal to customer support, citing a simple “edge case” fit of bad luck. But the judgment stands firm.

Cue the digital side-eye.

We’ve all been there, feeling accused of app fraud over some technical trip-up we didn’t see coming. But what are these “edge cases” anyway, and why can’t our smart tech handle them with more, well, intelligence?

Let’s dive deeper into why we shouldn’t blame algorithms for lacking psychic powers.

What the Heck Are Edge Cases?

Edge cases in technology refer to rare, extreme, or outlier scenarios that fall outside the bounds of normal or expected usage patterns. They live way out on the fringes of reality as the tech engineers imagined it when building their apps, devices, and code.

For example, what if a restaurant app lets you order a pizza with 1,000,000 toppings? Or your new stainless steel watch somehow corroded into a pile of goo the first time you wore it in the rain? Or your Roomba accidentally vacuumed up your entire living room carpet along with the dirt?

These situations seem pretty preposterous…unless you happen to be that 1 in 10 million edge case user to encounter them!

Why Can’t Tech Products Just Deal?

When edge cases strike, they often break functionality in weird, even comical ways. Just Google “software gore” images for a glimpse of creative meltdowns.

But to developers and designers, failures to handle edge cases well are no laughing matter. They represent potentially disastrous cracks in reliability and security.



Ewuranna Smith-Quayson

I write about my experiences, lessons, discoveries, stories I make up in my head, business stories and “how to” pieces. [Web Developer & Automation Lead by day]