When users search for a particular product on Google, a mixture of results will be returned. If a video is available that is particularly relevant to the user’s query, often one will be listed within the first page. This is despite the user not doing a specific search filtering the returned results to return videos (which of course would mean only videos would be returned).
Results that feature a video stand out because they also include a thumbnail image.
When you upload your video to YouTube, naturally if that video matches the query and is listed in the results, someone clicking on that link would be taken to YouTube.com - not your site. This is why private video hosting platforms like Vidbeo are particularly useful, since the user would be taken instead to your site.
This means you can drive traffic to your site and not lose those visitors - and potential customers - to YouTube.
We’ve written a blog post going into more detail about it: what is video SEO.