“How do you define programmatic, and what are its implications on the buy/sell process of digital signage?”
Programmatic, as it lives in the pure digital media world with live bidding against CPMs with near real-time audience metrics and dynamic ad-serving, is unlikely to live the same way in DOOH. More clinically, the best description for the immediate future of the DOOH buy/sell process is “Automatic.” This will be more about speed to market and triggering dynamic creative feeds versus the classic trading desk/open exchange environment.
There are significant and visceral real world characteristics specific to DOOH that will impact attempts to “Go Programmatic.” DOOH communicates in a one-to-many deployment versus a one-to-one interaction, which creates passive viewership in lieu of active viewership and relies on message frequency and momentum instead of one-off contextual moments, etc. There is a persistent desire to try and force-fit Programmatic into DOOH because of the money. DOOH has always had high revenue hopes, sometimes well beyond actual performance. Many see “Programmatic” as the savior. Most likely, it is just not that simple