Seeking reviews from online buyers? Ask later

Research from an information systems expert shows patience is a virtue in online reviews.

If you’re like most people, you enjoy a little public praise now and then. It’s the same for online retailers, but for them, stars and thumbs-up accolades are worth more than a momentary blush of pride. They’re crucial to gaining new customers.

A 2021 survey found that 91% of respondents will read at least one review before buying something, and an item’s score significantly influences the purchasing decision. That’s why it makes sense for online sellers to ask their buyers to write reviews, and often that request gets sent to the buyer’s email as the seller knows the item has been delivered. After all, people are likely to be most excited about a purchase as soon as they get it, and they’ll want to tell others about it right away, won’t they? No, they won’t.

Associate Professor of Information Systems Sang-Pil Han examined when sellers should push our reminders to buyers who haven’t yet posted a product or service review. His research shows that sellers will get better results by waiting a while before asking buyers to get online and critique what they’ve bought.

It’s about time

Part of this research was born from Han’s personal experience. He has found that sellers often ask him for a review before he’s even tried out the product. “I wondered if it would improve the response rate of review requests if businesses waited until customers had time to use the product or experience the service,” he explains.

Next, Han and his research colleagues wondered how long a business should optimally wait. “The key decision businesses have to make is to send the review request immediately after the product purchase experience or at some later time,” Han says. He added that there are pros and cons to each option.

Delaying the review request gives the customer time to experience the purchase and may serve as a needed nudge. “You may be considering a review — especially if you really like what you bought — but as time passes, memory fades away. You may need a reminder that prompts you to post that review,” Han says. “That’s the obvious advantage of a review reminder sent in a delayed manner.”

Conversely, reviews written closer to an experience — like a hotel stay or meal — are likely to contain more detail and be of higher quality because the consumer’s memory of the experience is still strong. Consequently, such reviews can be more valuable to the company being reviewed.

Still, people who post reviews voluntarily often need a little time to do that. In the write-up of his recent research, Han notes that an industry survey found most people took at least two days to post a review after receiving or using a product, and more than half took more than five days.

My time, not yours

Another reason to delay sending a review reminder: Sending such nudges too early can trigger psychological reactance. This push-back shows up when people are told what to do, and they perceive the instruction as a threat to their free will.

Han says he sees this often in his 7-year-old daughter. After school, he asks her, “Did you do your homework? Did you practice your violin?” Even if she was about to do it, she suddenly doesn’t want to anymore, Han says, adding, “That’s psychological reactance. People respond negatively because they feel the external force threatens their autonomy.”

It turns out that psychological reactance is why Han and his research team assumed that review reminders sent too quickly would be ineffective and counterproductive. “You were planning to share your experience so others could benefit,” Han says. In other words, reviewers often operate out of altruistic motives. “The moment you were asked to write the review, that request drove away your intrinsic motivation,” he continues. “Now, you don’t want to do it. The reminder turned you off.”

The study followed consumer responses to review reminders sent at various intervals. In one experiment, Han and his team analyzed review behavior on a South Korean travel site that offers tours and other adventures. The researchers randomly assigned users to receive a review reminder at one of several intervals: the day after the event, five days later, nine days later, or 13 days later.

Compared to the control group that didn’t get any review reminder, 6.32% of people who received a reminder the day after their event posted a review within a week, while 12% of the control group — the people who got no reminder at all — did the same, indicating that the reminder dampened enthusiasm to post opinions. The same type of disparity showed up in those who got reminders five days after the event, again showing that psychological reactance might have been in play for those who got the nudge before a week had passed.

When you get to the nine-day interval, there was no difference in percentages of those who posted reviews or not between the test group and the control group. But the rate of posts from those who got reminders 13 days after the event was significantly higher than those who received no reminder. The researchers ran a similar experiment with an online fashion retailer to test their theories with possible review posters purchasing from a different product category. Again, delayed review requests delivered a much higher percentage of reviews. With this site, the team also knew the ages and genders of reviewers. Using that data, they found that reactance appeared stronger in younger buyers and had a more significant negative impact on their review activity.

Han says the results of these experiments present a simple playbook for businesses that want customers to editorialize about what the company sells. “First, look back at historical data to find out how long it takes on average for customers to post a review,” he explains. That’s the baseline, and it should be the length of time in which no review reminder is sent. “Then the company has to run its internal experiment to find the optimal number of days to wait before sending out the review reminder.” Remembering that younger people reacted more negatively than older ones when prompted to write reviews soon after purchase, Han says that factoring in customer demographics might also be a good idea.

He says that following this playbook is worth a try, pointing out that delaying review requests costs a business nothing and could pay off handsomely. “That small difference in timing can make a huge impact,” he says. “This finding is relevant to any business that needs customer reviews, regardless of the company’s size.”