Why would politicians choose to use online videos to effectively convey a message?

In the last decade, politicians have been addressing issues and messages more and more, through the social media, or rather through the internet.

This is due to the popularity of the internet, and the ever-growing number of people that use it as a primary source of information, mostly the younger and the mid-age generations.

So it is logical that the politicians are following the trend, and try to deliver their messages and gain on popularity through the internet's social media, as there they can be seen, heard, read, by more people, than through the more traditional media.