The positioning of ad-supported digital out of home has always been in flux. As the industry began its ascent, it was considered an alternative to television advertising. The parallels were certainly there, given the reliance upon audio and video on a screen. Media buyers never got totally comfortable with DOOH versus TV, largely because the television buys were measurable (and confirmable via an advertising audit) if you had faith in Nielsen and Arbitron. DOOH required a certain leap of faith, even if its place-based nature added unquestioned value to advertisers.