In brief, we are inclined to go along with someone’s suggestion if we think that person is a credible expert (authority), if we regard him or her as a trusted friend (liking), if we feel we owe them one (reciprocity), or if doing so will be consistent with our beliefs or prior commitments (consistency). We are also inclined to make choices that we think are popular (consensus [social proof]), and that will net us a scarce commodity (scarcity).
While there are several platforms for doing this, clearly YouTube is the most popular for doing this. However, video marketing is also a great form of both content marketing and SEO on its own. It can help to provide visibility for several different ventures, and if the video is valuable enough in its message and content, it will be shared and liked by droves, pushing up the authority of that video through the roof.