The law
The Law
Every application has an inherent amount of complexity that cannot be removed. The only choice is where it lives: inside the system where engineers and designers wrestle with it, or out in the open where users must.
Two kinds
Inherent vs. Accidental Complexity
Some complexity is essential to the problem — booking a flight really does involve dates, seats, and fares. Accidental complexity is the extra friction we add on top. You can delete the accidental; you can only relocate the inherent.
The trade
Who Absorbs the Complexity?
Every design decision pushes the burden one way or the other. A blank text field is simple to build but hard to use; a guided flow is harder to build but effortless to complete. The work doesn’t go away — someone pays for it.
Best practice
Shift Complexity to the System
Smart defaults, autofill, format detection, and inference let the product do the heavy lifting. Every field you can pre-fill or compute is a decision the user never has to make — the burden absorbed where it belongs.
The trap
You Can’t Oversimplify It Away
Strip out essential complexity and it resurfaces as confusion, errors, or support tickets. A flow that hides necessary steps doesn’t remove the work — it just leaves the user to rediscover it the hard way.
Technique
Manage It with Progressive Disclosure
When complexity must reach the user, reveal it in layers. Show the common path first and tuck advanced options behind “More.” People get a simple surface without losing the depth they occasionally need.
✦
Tesler’s Law in the Age of AI
AI is the most powerful complexity-absorber yet — and the most tempting place to hide complexity the user still needs to see.
✦ AI Era
AI Absorbs the Complexity
A model can take a messy, ambiguous request and resolve the steps itself — the ultimate shift of complexity from user to system. “Plan my trip” replaces a dozen forms. The burden moves further toward the machine than ever before.
✦ AI Era
The Risk: Complexity Goes Hidden
When the model absorbs everything, the necessary parts can vanish too — the assumptions, trade-offs, and edge cases the user actually needed to weigh. Conservation still holds: surface what matters, with sources, controls, and an undo.