Should I Buy It?
We spend our time removing friction. Yet sometimes, friction is what protects us. Positive friction is the voluntary step you place between impulse and action — the space where conscious decision-making can exist.
Origin
The term friction in UX comes from Alan Cooper who, in The Inmates Are Running the Asylum (1999), introduced “cognitive friction” — any obstacle between the user and their goal. In this framework, friction is universally negative: the designer’s job is to eliminate it.
In 2010, Harry Brignull coined the term dark patterns to describe interfaces deliberately designed to deceive or manipulate users. These patterns exploit the inverse logic: adding friction where the user wants to act (canceling a subscription, deleting an account), and removing it where the platform wants them to act (subscribing, purchasing).
In 2022, Cass Sunstein formalized the concept of sludge in his eponymous book: friction deployed against the user, behind their back, to their detriment.
Positive friction is the individual response to these dynamics: deliberately adding obstacles to protect yourself from your own biases or external manipulation.
The Theory
Amazon’s Asymmetric Game
In 1999, Amazon patented the “1-Click Buying” button (patent US 5,960,411 — Peri Hartman + Jeff Bezos). Conversion rates exploded. The logic is straightforward: the less friction there is, the more people buy. Every step removed between desire and purchase increases conversion probability.
The same logic, reversed, explains the “Iliad Flow” — Amazon’s internal name for the Amazon Prime cancellation journey. Subscribing takes 2 clicks. Canceling: 4 pages, 6 clicks, 15 options (retention offers, cascading confirmations, deliberate slowdowns). The name references Homer’s Iliad — for the length of the journey.
Internal documents revealed during FTC v. Amazon showed that executives deliberately blocked improvements to the cancellation flow to maintain the friction. In 2025, Amazon settled for $2.5 billion.
Sludge vs Dark Patterns
These two concepts overlap but are distinct:
- Dark patterns (Brignull, 2010): deceptive interfaces designed to manipulate — the problem lies in design intent.
- Sludge (Sunstein, 2022): excessive friction deployed against the user — the problem lies in the effect on the user, whether intentional or not.
The EU’s Digital Services Act (DSA) and California’s CPRA have both integrated dark patterns into their regulatory frameworks.
BJ Fogg’s Behavior Model
BJ Fogg (Fogg Behavior Model, 2007) models behavior as: B = MAP (Behavior = Motivation × Ability × Prompt). Friction reduces Ability — the ease of completing the action. Reducing friction increases behavior probability. Adding friction reduces it.
This model is used by designers of addictive products (Nir Eyal, Hooked, 2014 — remove friction to create habits) and by those protecting themselves from their own impulses (positive friction).
In Practice
Positive friction means turning the platforms’ own tools around.
Concrete examples:
- Credit card in a separate drawer (online purchase = get the card = moment of reflection)
- 24-hour waiting rule before any purchase above a certain threshold
- Uninstall an app after each use — reinstall it only if you really want to use it again
- Should I Buy It: intercepts the “Add to Cart” button and asks 3 questions
In each case, friction doesn’t block the action — it creates the space between impulse and action. It’s in that space that conscious decision-making can exist.
Nuances and Limits
Positive friction only works if you chose it. Externally imposed friction (by someone else, by regulation) generates resistance, not reflection. Its effectiveness comes from ownership — “I imposed this rule on myself because I decided it in a cold state.”
It can be bypassed. If motivation is strong enough (or the impulse intense enough), you’ll cross the friction without pausing. It’s not an absolute safeguard, but a probability of pause.
The complexity paradox. Adding too many positive frictions creates cognitive load — which can itself become a problem. The goal isn’t to slow everything down, but to slow down the specific moments where impulsive decisions have significant consequences.
Sources: Cooper, A. (1999). The Inmates Are Running the Asylum · Brignull, H. (2010). deceptive.design · Fogg, B. J. (2007). Fogg Behavior Model · Eyal, N. (2014). Hooked · Thaler, R. & Sunstein, C. (2008). Nudge · Sunstein, C. (2022). Sludge. MIT Press · FTC v. Amazon settlement (2025)