What 'invite a friend to unlock' does to your matches

You open a dating app and see a badge. Three people looked at your profile, and one sent a message. Tap it, and the app offers a deal: pay for a month, or invite friends until enough of them join, and the message is yours.

That screen is a pricing decision, and one dating site tested it on its own members. The harder the site made it to unlock, the more money it collected and the less everyone dated.

The experiment

For a 2015 launch in a major European city, a selective dating site that screened new members by hand gave each newcomer a randomly assigned referral rule. Some had to bring in one approved friend before they could see who had viewed their profile or messaged them. Others had to bring in more. A further round of friends unlocked winks and matches. Under every rule, a paid subscription opened everything.

Rodrigo Belo and Ting Li followed 52,782 new members through their first eight weeks and published the results in Management Science in 2022. The paper does not name the site.

What a higher bar did

Asking for more friends did what the site wanted on paper. Members sent more invitations, more of those friends joined, and more members paid. Moving from a one-friend rule to a three-friend rule raised what the average new member paid.

It also made the site quieter. Members on the stricter rules visited less, looked at fewer profiles, and sent fewer messages, winks and likes. They made fewer matches too, whether a match meant a mutual like or a real back-and-forth of messages. The paper's tables give the size of each shift.

The drop was not spread evenly. Under the stricter rules, members who went out and recruited friends used the site more. The pullback came from members who paid and from members who did neither.

The harder the site made it to unlock, the more money it collected and the less everyone dated.

Why your matches feel it

The authors point to two possible explanations. A higher bar meant members waited longer to see who had written to them, and members who could not read their messages logged in less. Once someone unlocked premium, they used the site more. Members with friends on the site also stayed more active, and a stricter rule left the paying members with fewer friends there.

The part that reaches you is what happens next. A dating site is only as good as the people answering. Every member who stops logging in because a message sits behind a gate is someone who is not replying to anyone else. In the authors' words, members became less engaged, "decreasing the value of the platform for all users."

A locked inbox is not only a cost to the person staring at it. It thins the room for everyone, which is the gap we wrote about in engagement metrics vs. relationship outcomes: an app can make more money while the thing you came for gets harder.

What this does not show

This was one site in one city, measured over each member's first eight weeks. It counted visits, messages and matches inside the site, not relationships, and the authors note that people also go quiet on a dating site because they met someone. Whether a large app works the same way today is an open question.

Reading the gate on your own app

When an app shows you that someone wrote and then asks for money or friends before you can read it, that wall is where the company decided to put its price. On this one site, a stricter gate went with quieter weeks, so a slow week behind one may say more about the gate than about you.

Inviting a friend is a fair trade only if that friend wants to date there. On this site, friends who joined under the stricter rules paid and visited about as much as anyone else, so a higher bar did not bring in worse members. It asked more of the people already inside, and the ones who paid or waited came back less often. If you decide to pay or invite, decide early. On this site, members used it more once they could see who had written to them, and every week spent behind the gate was a week of messages going unanswered.