Great and very important question. Assaf did a great job with his answer, so most of my points below are agreeing with him, but I have a few extra nuggets ;)
1. The first thing you need to do is clearly define your target audience for the video and how you are going to use the video. Do the people watching this video know anything about your company? Or will this video likely be their first introduction to you? This will help you decide how much of the video is explaining who you are and what you do vs. why your viewer should take the next step with you (I'll go into more detail on this in a later point). You also need to understand how the video will be used. Will you be emailing this to sales leads? Will this be prominantly displayed on your homepage or acquisition funnel on your website? Will you be using this video as a video ad? Once you have this defined you can more easily craft the video.
2. Do competitive research! No need to re-create the wheel here. What do your competitors do in their videos? Just because they do something doesn't mean it's good... but it will give you an idea of what your audience may be accustomed to. If you feel like your competitors all leave out a key pain point that you've identified, you can key in on that and use that as a differentiator. You should also assume that your potential customers might be comparing you to your competion based on your video, so make sure you come out on top by crafting your video with your competitors' videos in mind. I've included some example explainer videos that I helped create at a recent startup as references:
This is our first version when we were just starting out with a very small budget (~$500): https://www.youtube.com/watch?v=CWUlmxBMV04
This is our most recent video with a much larger budget (~$3000): https://www.youtube.com/watch?v=M-DfLOco4dk
3. Make sure your video is short and sweet. No longer than 2 minutes. May even need to be shorter depending on how you expect to use the vide0 (see point 1). The more engaged your audience, the longer you can allow the video to be.
4.Always have a call to action. At the end of the video what do you want the person watching to do? Sign up for an account? Start a trial? Call you for a demo? Make sure you are explicit with what you want your audience to do.
5. This may be obvious but if you are launching globably think about the language you should use in the video. Are you going to have it voiced over in multiple languages? Typically if you want to go with English but have clients in Europe a voice actor with an English accent (i.e. from UK) plays better with that audience as it feels more local then someone from the US (and typically people in the US like it too).
6. Personally I wouldn't describe your competitors or go into what they do or don't have for a few reasons: First, if your audience doesn't know about your competitor, they do now! Second, it might shorten the "shelf life" of your video as you don't control your competitor's product or roadmap so if you say you have something they don't, that could only be true right now and might be false quickly (and then you might need to pull the video).
I have a lot more thoughts here. Let me know if you'd like to chat further!