4 Out of 5 Viewers Leave If a Stream Buffers Once

Whatever happened to patience? More than 81 percent of all online video viewers click away if they encounter a clip rebuffering, according to a new study by Tubemogul. The Emeryville-based video distribution and analytics startup took a close look at 192 million video streams over the course of 14 days to figure out how much rebuffers matter. The result: 6.81 percent of all streams rebuffer at some point, and around 2.5 percent rebuffer twice.

Tubemogul also measure how many times rebuffers occur across several popular CDNs. During its tests, Limelight (s LLNW) performed the best, while Bitgravity’s streams had to reload the most, with Akamai (s AKAM) being somewhere in the middle.

Tubemogul’s research is based on both short-form content as well as TV shows and other longer streams. The company told me that it wasn’t able to give any specifics as to how people interact with buffering in different situations, so we won’t know, for example, if users are more forgiving with Hulu streams than with YouTube videos.

However, Tubemogul was able to measure some significant differences between various popular CDNs. Only 3.84 percent of all Limelight streams sampled for the analysis rebuffered, it said. Streams served by Akamai were interrupted roughly twice as often (7.96 percent), while Bitgravity took the dubious honor of being the CDN with the most instances of rebuffering (12.48 percent).

Those numbers are pretty significant, especially now that we know that most viewers don’t bother to stick around for a video to start playing again. As Tubemogul’s marketing director David Burch noted, “To advertisers, this means many post-rolls are routinely never seen.”