How long should a video be? Well, that reminds me of a story.  Last week, I spoke at SES London 2013 at a conference session entitled, “Keys to Success with B2B Video” and during a ClickZ express clinic entitled, Optimising Video for Maximum Visibility.” I also participated in two Roundtable Forums that enabled attendees to Meet the Experts: one on “Branding Through Social Media” and the other on “Video Optimization.”  And one of the questions that I was asked again and again and again was: “How long should a video be?”

Is There A ‘Right’ Answer for Video Length?

This isn’t surprising. This has been a popular question since at least 2009, when I tackled it in the first edition of my book, YouTube and Video Marketing: An Hour a Day. (I said, “Keep videos 2 to 3 minutes long.”) And it was still a popular question in 2011, when I addressed it again in the second edition of my book. (I said, “Long enough to reach a point.”)

But the question took on a new urgency in October 2012 when “watch time” replaced “view count” in the YouTube algorithm.

As Eric Meyerson, YouTube’s head of creator marketing communications, explained back then,

“Now when we suggest videos, we focus on those that increase the amount of time that the viewer will spend watching videos on YouTube, not only on the next view, but also successive views thereafter.” He added, “If viewers are watching more YouTube, it signals to us that they’re happier with the content they’ve found. It means that creators are attracting more engaged audiences. It also opens up more opportunities to generate revenue for our partners.”

Get it? Got it? Good.

So, how long should a video be?

I thought that I had answered this question three months ago when I wrote a column entitled, “What’s the Ideal Length for a YouTube Marketing Video? A look into Video Duration vs. Social Sharing.“

In that column, I interviewed David Waterhouse, the Head of Content for Unruly Media, who had just compiled some interesting stats on the average length of the ads in the Top Global Video Ads Chart. He found that the average length of the Top 10 most shared ads of all time is 4 minutes and 11 seconds, if you exclude “Kony 2012,” which is 29 minutes and 59 seconds long.

And the day before SES London 2013 began, I visited Unruly Media’s new digs at 42-46 Princelet Street in London to get a tour of Unruly’s Social Video Lab. I spoke with Ian Forrester, Unruly’s Global Insight Lead, and we discussed why the shorter the ad, the fewer shares it tends to attracts.

Recent research has found that the number of shares a video gets is linked to the strength of emotion it elicits from its viewers. The stronger the emotion, the more likely it is going to be shared. So, it appears that 30 seconds may not be enough time to tell a compelling story that generates a very strong emotion.

Forrester and I also discussed David Ogilvy’s classic book, Ogilvy on Advertising

Widely hailed as “The Father of Advertising,” Ogilvy said back in 1985, “For all their research, most advertisers never know for sure whether their advertisements sell. Too many other factors cloud the equation. But direct-response advertisers, who solicit orders by mail or telephone, know to a dollar how much each advertisement sells. So watch the kind of advertising they do.”

A generation before the advent of social videos, Ogilvy observed, “General advertisers use 30-second commercials. But the direct response fraternity have learned that it is more profitable to use two-minute commercials. Who, do you suppose, is more likely to be right?”

So, I thought I was ready to answer the question: “How long should a video be?”

Then, Oliver Snoddy, the Head of Planning at Twitter UK, gave the morning keynote at SES London 2013 on Wednesday, Feb 20. And he quoted John Hegarty, one of the world’s most awarded and respected admen and the author of Hegarty on Advertising.

According to Hegarty, “Creativity in advertising is all about the power of reduction. Write less, say more.”

And Snoddy added, “Constraint inspires creativity.”

He demonstrated that “a single Tweet can tell a story” with an example from the Oreo Cookie account on Twitter.

When the power outage stopped this year’s Super Bowl for 34 minutes, Oreo posted a simple ad that was retweeted more than 16,000 times on Twitter. The message:  “Power Out? No Problem” accompanied with a picture that said, “You can still dunk in the dark.”

But instead of a picture, imagine if that Tweet could have been accompanied by a short video from Vine, the new iPhone app that lets you create and share looping videos that are 6 seconds long. You can dunk an Oreo cookie in the dark in six seconds.

Or use Tout, which ups the limit to 15 seconds. What can you say in 15 seconds? Check out “Oreo Fudge Cremes Commercial – Indescribably Good! (15 sec)”

And, if you mistakenly think that a B2B brand can’t tell a compelling story in six seconds, then check out “Happy 540th birthday to Nicolaus Copernicus!” General Electric made with Vine.

So, how long should a video be?

After SES London 2013, I now think that the right answer is: “Long enough to reach a point.”

That’s also the advice provided by the video, “NPR’s Scott Simon: How to Tell a Story” which is part of the YouTube Reporters’ Center.

Simon says, “A story ought to have a point. I don’t mean a lesson or a moral or even a punch line, but a point – something that people can take away from it.”

So, how long does it take to reach a point?

Like “Happy 540th birthday to Nicolaus Copernicus,” it can take 6 seconds. Or, like “Kony 2012,” it can take 29 minutes and 59 seconds. Or, like most videos, it can be somewhere in between.

In other words, put away your stopwatch and start making great videos that your audience will love and share. Then, check early and often on the Time Watched report in YouTube Analytics.

You can use this data to better understand what your audience wants to watch. More time watching content means a more engaged audience and more ad revenue. That’s what YouTube’s focus on watch time is all about.

Get it? Got it? Good.