Marshall McLuhan famously explained that “the medium is the message.” Although his context was not my context, the idea still applies perfectly.
Over and over again, I observe that marketers of all types make the mistake of not fitting or adapting their messages to a new medium. Every medium has its own requirements and imperatives for being used most effectively. If your messages are not re-shaped and stylized to fit some medium other than the medium of origin, your message will lose impact and focus.
The ephemeral nature of the live spoken word may require that you use more words to let listeners follow the thought trail and keep up. The persistent and referential nature of the written word allows you to tighten up the prose because readers can go at their own paces and re-read as necessary to maximize absorption. This is a big deal for marketers, where every medium counts and where you should always be concerned about bang-for-buck metrics.
Respect every medium. Use its unique potential in your messaging ensemble.