The IKEA Effect in Marketplace UX — Why Making Users Do More Work Can Increase Trust

Everything we know about marketplace UI/UX design says the same thing: reduce friction. Fewer steps. Fewer clicks. Fewer decisions.

Most of the time that’s right. But there’s one scenario where the opposite is true — and most product design teams miss it completely.

---

The IKEA effect

In 2011, researchers at Harvard discovered something counterintuitive. People who assembled IKEA furniture valued it 63% more than identical pre-assembled furniture. Not because it was better. Because they built it.

The effort created ownership. Ownership created attachment. Attachment created value that didn’t exist in the product itself.

This principle applies directly to marketplace platform development — and almost nobody uses it intentionally.

Where friction creates trust

We noticed a pattern across multi-sided platform builds that process $720M+.

The platforms that asked users to do slightly more during onboarding had higher retention than the ones that optimized for speed.

A seller who spends 8 minutes completing a detailed profile treats the platform differently than one who listed in 90 seconds. They respond faster. Stay longer. Churn less.

A buyer who sets preferences, saves favorites, and customizes search comes back more often than one who browsed anonymously. The UX architecture let them invest something. And people don’t abandon their investments easily.

Good friction vs bad friction

Bad friction is any step that exists because nobody thought to remove it. A redundant form field. A confusing navigation path. A web design pattern that asks for information the platform already has.

Good friction is a moment where the user invests something meaningful — time, identity, preference, reputation — and gets back a sense of ownership.

Bad friction: “Enter your address, phone, company name, and tax ID before you can browse.”

Good friction: “Tell us what you’re looking for so we can show you better results.”

Same effort. Completely different emotional outcome in the user experience design.

Three places where intentional friction works

1. Seller onboarding

We tested two approaches on a marketplace web platform. Version A: list in 60 seconds, minimal fields. Version B: guided setup with profile photo, bio, and a short verification step.

Version A had more signups. Version B had more sellers who actually transacted. Their average time on platform was 4x longer.

The sellers who invested in their profile treated the platform like a business tool. The rest treated it like an experiment.

2. Buyer personalization

On a consumer marketplace we added a 3-step preference flow after signup. Every UX design best practice says this is friction.

Repeat visit rate went up 35%.

The platform felt personalized from session two. The user had invested their preferences — and the custom softwareremembered. That’s not friction. That’s a relationship.

3. Verification as a trust signal

Most platforms treat ID verification as a compliance checkbox. We designed verification as a trust UX moment in our app development process. After completing it, the user sees: “You’re now verified. Verified sellers get 3x more views.”

The effort becomes an investment with a visible return. The user earned status. And status is something people protect.

When to reduce and when to add

Reduce friction on the path to the transaction. Everything between “I want this” and “I bought this” should be fast. No unnecessary steps in the mobile design or web design.

Add friction on the path to commitment. The moments where a user goes from “I’m browsing” to “this is my platform” — that’s where intentional effort in marketplace UX design pays for itself.

What this means for marketplace product development

Stop treating all friction as the enemy.

A seller who invested 10 minutes in their profile doesn’t leave for a competitor over a 2% commission difference. A buyer who saved 15 favorites doesn’t start over somewhere else.

That’s not lock-in. That’s ownership. And ownership is the cheapest retention strategy in marketplace design and development — because the user built it themselves.

---

U1CORE is a product design and development studio specializing in marketplace platforms. We offer custom product UI/UX design, web design, mobile design, custom software development, app development, branding development, and product audit. $720M+ processed through products we’ve built.