Design For Humans, Not Spherical Cows
Real users don’t live in models. They live in the mess those models often ignore.
Most systems don’t break because someone made a mistake after launch. They break because the system was broken at the thinking stage.
The biggest mistake I see in user experience is people designing systems for idealized humans who don’t exist.
It reminds me of an old physics joke where a farmer asks some scientists for help improving milk production. They go off to investigate, then come back and say:
"Alright, we can solve your problem... assuming perfectly spherical cows in a vacuum."
Cool... Except:
Real cows aren’t spherical.
Real environments aren’t vacuums.
The joke highlights a common pitfall: oversimplifying complex problems to fit neat models, at the expense of real-world applicability.
Similarly, when we design for user experience, there’s a tendency to create models based on idealized user behaviour — assuming users are always rational, consistent, and intuitively aware of every next step.
We even give these model users names, to make them feel more human.
But that human isn't real.
Real users are diverse, unpredictable, and operating inside sometimes chaotic, often layered environments, driven by their own personal abilities and constraints.
By designing systems for "spherical cows," we risk creating solutions that fail real humans — the ones who forget, guess, get frustrated, give up, or quietly build invisible workarounds no one maps.
Segmentation is Survival
You don’t just need to understand your users. You need to understand how they think differently from each other — and why.
Real segmentation means:
Knowing not everyone processes information the same way.
Seeing how shared needs, not surface labels, naturally group people.
Planning for differences not enforcing sameness.
If you aren’t actively segmenting your users by experience, behaviour, and constraints, you’re not serving them. You’re dragging them.
Invisible Labour Is Infrastructure
The real threat isn't the problems you know about. It's the ones hidden under the surface, where quiet excellence makes what's broken seem functional.
Many organizations survive today because someone you don’t see is:
Fixing your data inputs by hand.
Catching edge cases that shouldn't exist.
Translating across broken team assumptions without credit.
That labour isn’t optional. It's the hidden infrastructure your system stands on. If you haven't mapped it, you're already at risk.
Intrinsic Motivation is a System Output, Not a Personality Trait
If you want people to care, you have to show them that their growth matters.
You have to systemically build environments where:
Mastery is normal.
Investment is visible.
Autonomy is respected.
People adopt and grow within systems when the system itself builds capacity, not just demands loyalty.
You want customer success? Build internal success first.
You want loyalty? Build a system that earns it.
You want adoption? Solve real human frictions.
Systems that are invested in the people they serve create self-sustaining excellence. Systems that don't collapse from the inside.
Design for humans you actually have in their real environments, not for spherical cows in a vacuum.