user5113: If I'm making 4-minute videos and everybody's dropping off after 2, then I'm doing something wrong. However, I notice that sometimes I watch a much longer video, often because the quality of the narrative is so good. When trying to craft engaging content, what factors influence a viewer to watch the video to then end?
Here are some factors I've considered:

Shot variety such as B-roll and multiple camera angles
Music
Dramatic tension
Authentic responses to interview questions (in a mini-documentary)
Production value (color grading, audio mix, etc.)
Motion graphics
Video length


user3481: There are already good answers. But let me share what not to do.
Too often than not there is something poisoning our videos. We have so much to say, but the video should be less than x minutes. As a result we squeeze as much as possible into this precious time. We don't even realize how indigestive the video has become, because we are too much into the subject.
I have seen this on my own videos, but was surprised to see it on videos of well-known professionals, too.
This is what I added to my to-do list for my next videos:

Reduce the many messages to one core message
Elaborate that message from different angles instead of adding new stuff
Have time for creating an atmosphere
Less talking heads, more showing what they do
Have a hook at the beginning that will be resolved at the end (ideally by the core message)
If the video is longer, have additional smaller hooks & resolutions in between

That's a lot, I know. If we take a 3-min. video, there's not so much time for talking. It really needs discipline.

user3908: Content trumps everything. People will watch if the story is compelling. 
You can have crap audio, blocky graphics, bad lighting, noisy video etc but it all falls away if you have something to say that an audience wants to hear.
Naturally it's always a good idea to do the best job you can in all the technical areas because you don't want to actively annoy your audience, and they come to you with certain expectations driven by top-level production in video and film, but technique by itself is never enough.

user11372: There could be any number of factors as to why people quit watching a video, but if you want to entice them to stick around, there are a few tricks.

Yes, "content is king," but CONTEXT is arguably queen— and let's be honest, who really rules the castle? That is to say— even if your content is great, if you aren't getting it to the right audience, it won't matter. Make sure the people who would WANT to see your video are finding it at the right time and place. Context.
Pay-off. A viewer is more likely to stick around if they know the pay-off at the end of the video is worth it. What will they learn? What mystery will be solved? What's the burning question? etc. Give them a clue in the beginning.
Challenge? As a twist to the "pay-off" bit (and especially if your end goal is social media shares and conversions)... Remember the whole KONY 2012 thing? They got millions of people to watch a 20-something minute documentary, and then spread it virally. Why? Beyond just compelling content: they challenged the viewer to finish it at the very beginning. The first lines were similar to "The following video is a social experiment..." I.E. "Let's see who makes it all the way through and then cares enough to do something about it." 

It was a challenge, and human nature led people to take it on.
So there's my 2 cents.

5113: <p>If I'm making 4-minute videos and everybody's dropping off after 2, then I'm doing something wrong. However, I notice that sometimes I watch a much longer video, often because the quality of the narrative is so good. When trying to craft engaging content, what factors influence a viewer to watch the video to then end?</p>

<p>Here are some factors I've considered:</p>

<ul>
<li>Shot variety such as B-roll and multiple camera angles</li>
<li>Music</li>
<li>Dramatic tension</li>
<li>Authentic responses to interview questions (in a mini-documentary)</li>
<li>Production value (color grading, audio mix, etc.)</li>
<li>Motion graphics</li>
<li>Video length</li>
</ul>
 3481: <p>There are already good answers. But let me share what <em>not</em> to do.</p>

<p>Too often than not there is something poisoning our videos. We have so much to say, but the video should be less than x minutes. As a result we squeeze as much as possible into this precious time. We don't even realize how indigestive the video has become, because we are too much into the subject.</p>

<p>I have seen this on my own videos, but was surprised to see it on videos of well-known professionals, too.</p>

<p>This is what I added to my to-do list for my next videos:</p>

<ul>
<li>Reduce the many messages to one core message</li>
<li>Elaborate that message from different angles instead of adding new stuff</li>
<li>Have time for creating an atmosphere</li>
<li>Less talking heads, more showing what they do</li>
<li>Have a hook at the beginning that will be resolved at the end (ideally by the core message)</li>
<li>If the video is longer, have additional smaller hooks &amp; resolutions in between</li>
</ul>

<p>That's a lot, I know. If we take a 3-min. video, there's not so much time for talking. It really needs discipline.</p>
 3908: <p>Content trumps everything. People will watch if the story is compelling. </p>

<p>You can have crap audio, blocky graphics, bad lighting, noisy video etc but it all falls away if you have something to say that an audience wants to hear.</p>

<p>Naturally it's always a good idea to do the best job you can in all the technical areas because you don't want to actively annoy your audience, and they come to you with certain expectations driven by top-level production in video and film, but technique by itself is never enough.</p>
 11372: <p>There could be any number of factors as to why people quit watching a video, but if you want to entice them to stick around, there are a few tricks.</p>

<ol>
<li><p>Yes, "content is king," but CONTEXT is arguably queen— and let's be honest, who really rules the castle? That is to say— even if your content is great, if you aren't getting it to the right audience, it won't matter. Make sure the people who would WANT to see your video are finding it at the right time and place. Context.</p></li>
<li><p>Pay-off. A viewer is more likely to stick around if they know the pay-off at the end of the video is worth it. What will they learn? What mystery will be solved? What's the burning question? etc. Give them a clue in the beginning.</p></li>
<li><p>Challenge? As a twist to the "pay-off" bit (and especially if your end goal is social media shares and conversions)... Remember the whole KONY 2012 thing? They got millions of people to watch a 20-something minute documentary, and then spread it virally. Why? Beyond just compelling content: they challenged the viewer to finish it at the very beginning. The first lines were similar to "The following video is a social experiment..." I.E. "Let's see who makes it all the way through and then cares enough to do something about it." </p></li>
</ol>

<p>It was a challenge, and human nature led people to take it on.</p>

<p>So there's my 2 cents.</p>
