The majority of our videos do include music, but that’s not to say that every video has to. And we see examples all the time of videos with too much music.
The important thing is not to distract from what you’re saying.
If music helps the flow of a video - for example, by punctuating the end of one section and the start of another - or if it helps to create the right mood or elicit the emotional response you’re looking for, then yes, used sparingly, it can be very effective.
On the whole, instrumental music is best. Fast, upbeat music is generally preferable to slow or classical music, but there are no hard-and-fast rules and tastes, of course, are personal.
We usually choose music ourselves which we think is appropriate, though we obviously offer alternatives if you don’t think it works.
We also pay up-front for rights to any tracks we use, so you don’t have to worry about royalty payments.