Should every onboarding question say why you're asking?

Yes. Every onboarding question should say why you are asking and what the person gets from answering. In Ellen Langer's copier experiment, asking to cut the line with no reason got 60% yes, and adding a simple reason ("because I'm in a rush") got 94%. People give their time, so they need to know why a question matters to them. Tell them how answering helps them.

Every question needs to be clear about the value it brings to users. Why are you asking this? What do I get from it? I'm Michael Berliner. This is one of the ten principles from my talk at Business of Apps in New York, built on teardowns of over 100 apps, and "explaining why" is one of the three opportunities I see people miss most.

Does giving a reason really change whether people say yes?

Yes. Ellen Langer, in a famous experiment, had people ask to cut the line at a copy machine. When someone just asked, "Can I use the copier?" 60% said yes. When they asked with a simple line, "Can I use the copier because I'm in a rush?" 94% said yes. Just asking someone gets you some opt-in. Asking them and giving them a reason why gives them justification to really oblige.

Is it worth the extra reading in onboarding?

Yes. Take a birthday question. Option A is simple and straightforward, "When's your birthday?" and it doesn't overload them with information. Option B adds copy below saying why you are asking. It is more to read and a bit more mental load, but also more explanation. The one that explains why it is valuable to them does better: why are we asking, what does it mean, and what does it matter to them? Of course it makes sense, and yet many people, in many onboardings, don't do this.

What makes a good reason?

It tells the person how answering helps them, not just that you need it. Why are you asking for my birthday? Why are you asking for my habits? Why are you asking for notification permissions? It is not just about giving a standard reason. It is about communicating back why it actually helps them. That is how you start building a trust relationship, where they know from the very beginning that you are looking out for them and want them to succeed.

What does a good version look like?

Strava gives three specific reasons why it is asking, and it also has a privacy line, which makes you feel more confident and committed.

Runna ties its workout-frequency question to injury risk.

When does the reason matter most?

Where it is unclear what value answering gets you. Put the reason in the header or subheader. The notification permission is a bigger ask than entering your name, which is why apps give it a dedicated primer screen: see how to get more people to allow notifications. For the rest of the flow, see what makes subscription app onboarding convert.

What to do with it

On every question, tell them why you are asking and what they get from it.

FAQ

Should every onboarding question explain why it is being asked? Yes. Tell people why you are asking and what they get from it, or they are just giving you information without a reason.

What is the evidence that a reason helps? Ellen Langer's copier experiment: asking to use the copier got 60% yes, and asking "because I'm in a rush" got 94%.

What does a good reason look like in an app? Strava gives three specific reasons for the question it asks, plus a privacy line that makes people feel more confident and committed. Runna ties its workout-frequency question to injury risk.

Michael Berliner advises founders and product leaders at consumer subscription apps on growth, pricing and product strategy through Otter Growth Advisory.