Netflix Increased Watch Time 20% By Testing Title Images With Subscribers

Netflix is bullish on improving subscribers’ watch experiences through testing. According to a report from Variety, the streaming service conducted around 150 optimization split tests in 2015 alone to see how subscribers responded. One test in particular proved extremely useful and proved good thumbnail images aren’t just a necessity on YouTube. When Netflix tested new images for select titles with a group of subscribers, average viewing time on those titles increased by at least 20%.

Back in 2013, Netflix realized traditional DVD box cover art provided by Hollywood studios often wasn’t enough incentive to get the platform’s subscribers to watch a title. This lack of visual appeal became a company concern, because, as Netflix Chief Product Officer Neil Hunt told Variety at CES 2016, “we have 30 seconds, 60 seconds or 90 seconds to capture your interest.” If images couldn’t capture a subscriber’s attention in those first 90 seconds, the chances were those members might just turn off Netflix or close out of its app all together.

So the streaming service replaced standard DVD box cover art on subscribers’ dashboards with a wider selection of more appealing, striking images of studio assets or film/show screenshots. More recently, Netflix has started testing which specific images should display. Netflix team members gather about six images for each of the platform’s titles, and then test them with a small subset of subscribers. The images that result in more subscriber interaction with the title are then used across the board for all Netflix subscribers. This simple test improved watch time anywhere from 20-30% on titles with user-tested images.

Netflix’s image title test has so far turned out to be one of the platform’s most successful optimization methods to date. Other tests, however, weren’t as fruitful. For example, Netflix tried customizing title selections based on individual subscribers’ schedules, assuming one household wouldn’t watch a whole TV series during something like a traditional Saturday night movie slot. The streaming service had to increase internal computations by almost 50 times to provide these recommendations, but ultimately discovered there was almost no improvement in watch time.

Hunt told Variety subscribers are simply too used to binging content, no matter what hour of the day it is. “So much of Netflix is binging on a series,” Hunt said. “We don’t need magic for that.”