New York Times programmatic advertising director on technology challenges and native ad unit, Flex Frame

The New York Times is addressing a lot of the trends that are currently surging the programmatic industry right now. Speaking to its director of programmatic advertising, Sara Badler, she expresses that the biggest challenge right now is with the technology platforms.
Badler says publishers and marketers are 'ready, willing and set up to transact' but the question lies in the execution. 
What have been the biggest challenges in programmatic sector of the industry has had to conten