Category
Cognitive Principles
How attention, memory and mental load decide what a visitor notices, understands and remembers.
31 principles
Cognitive Load Theory
The brain has a limited processing budget — demand too much and performance collapses.
Read →Loss Aversion
The pain of a loss is roughly twice as strong as the pleasure of an equivalent gain.
Read →Social Proof
People look to what others do and say to judge the right course of action, especially when unsure.
Read →Anchoring Effect
The first number or fact a person sees disproportionately shapes every judgement that follows.
Read →Authority Principle
People defer to credible, knowledgeable sources — credentials and expertise build trust and compliance.
Read →Scarcity Principle
Things that are rare or running out are perceived as more valuable — genuine limits create urgency.
Read →Reciprocity Principle
People feel pulled to return a favour — give something of value first and the urge to reciprocate is strong.
Read →Commitment & Consistency
Once people make a small commitment, they act to stay consistent with it.
Read →Liking
People say yes more readily to those they like — warmth, similarity, and genuine personality matter.
Read →Choice Overload (Paradox of Choice)
Too many options causes paralysis — people often choose nothing when faced with abundance.
Read →Mental Models
Users arrive with expectations from past experience — break those without reason and you cause confusion.
Read →Confirmation Bias
People notice and favour information that confirms what they already believe.
Read →Choice Architecture
The way choices are presented inevitably shapes what people choose — there is no neutral design.
Read →Default Effect
People disproportionately stick with whatever option requires no action — the default wins by inertia.
Read →Status Quo Bias
People prefer things to stay as they are — any change feels like a loss, even when change would benefit them.
Read →Sludge (Friction as a Dark Pattern)
Deliberate or negligent friction that makes it harder for users to reach an outcome that's in their interest.
Read →Present Bias
People heavily overweight immediate costs and benefits against future ones — the near future crowds out the far future.
Read →Informational Cascades & Social Norms
People infer what's correct or normal from what they see others doing, and cascade behind it — making visible behaviour contagious.
Read →Commitment Devices
Giving people a way to pre-commit to a future action increases follow-through by locking in their intention before temptation arrives.
Read →Involuntary Attention (Peripheral Motion Capture)
Movement, contrast, and faces in the periphery capture attention automatically — before conscious decision-making kicks in.
Read →Face Recognition & Human Presence
The brain has dedicated neural architecture for detecting and processing faces — they receive instant, preferential attention and signal trust and humanity.
Read →Flow State
When conditions are right — clear goal, appropriate challenge, no interruptions — users reach a state of deep, effortless engagement that is intrinsically rewarding.
Read →Dopamine & Anticipation
Dopamine is triggered more by the *anticipation* of a reward than by the reward itself — unpredictability amplifies the response.
Read →Unconscious Decision-Making (Emotion Precedes Reason)
Most decisions are made unconsciously and emotionally first — the conscious mind constructs reasons afterwards.
Read →Internal Triggers
The most powerful reason to return to a product is an emotional itch it has trained users to associate with it — boredom, loneliness, uncertainty, FOMO.
Read →Fogg Behavior Model (B = MAP)
Any behaviour — including clicking a CTA — requires motivation, ability, and a prompt to be present simultaneously; if any one is missing or too weak, the behaviour won't happen.
Read →Variable Rewards
Unpredictable rewards engage far more deeply than predictable ones — the anticipation of a possible reward, not the reward itself, drives compulsive return.
Read →Investment & Stored Value
The more a user invests in a product — data, preferences, content, connections — the harder it is to leave and the better the product gets for them.
Read →Actions Before Attitudes
Attitudes follow actions, not the other way around — if you want people to feel differently about something, get them to do something small first.
Read →Barrier Analysis
Before designing any conversion solution, you must diagnose exactly what prevents the target behaviour — generic friction reduction fails when the actual barriers are specific and unaddressed.
Read →Moment of Power (Intervention Timing)
People are most receptive to change at specific moments — life transitions, task beginnings, decision points — and interventions timed to these moments outperform identical interventions timed badly.
Read →See these principles on your own site
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