LOS ANGELES – Taco Bell CMO Marisa Thalberg knows that despite viewing shifts, traditional television is still a powerful medium for the fast-food giant. What she finds “very scary” is spending money on digital platforms given issues like viewability, fraud and the potential for the company’s ads to appear in the wrong environment.

“TV’s still really powerful for us. It’s still the most mass reaching audience for us and it still works for us,” says Thalberg.

Turns out you don’t need complicated measurement and attribution metrics to tell whether a particular advertising medium works, Thalberg explains in this interview with Beet.TV at the annual Transformation conference of the 4A’s.

“You feel it right away when we have a limited time offer coming up and we have a big a launch,” says Thalberg. “If the media is not kind of working and the message isn’t working, we know within a few days.”

She refers to this kind of feedback Taco Bell’s direct response model. “It’s not a pure correlation, but it’s about as close as you can get without the perfect data science behind it,” says Thalberg.

While acknowledging the profound changes that social media has fostered in how people and brands connect and communicate with each other, Thalberg sees “a bit of a morass” right now in the digital space.

“I think there are really big, dark clouds that are hovering over our industry right now that make it very scary to be putting money into the marketplace,” she says.

Within these clouds are the issues of viewability, fraud and “the recent issues that have impacted a lot of brands, including mine, in terms of the trust of appropriate context where your ads get placed in a Google or YouTube environment.”

Nonetheless, these digital stalwarts continue to be a key partner for Taco Bell. “But we need to figure out a way that someone in my job, or someone right under me, don’t have to be tending this like giant acre garden of every little detail and still feel like we can be confident that our message is where it should be,” Thalberg says.

This video is part of series produced in Los Angeles at the 4A’s Transformation ’17. The series is sponsored by Extreme Reach. For more videos from the conference, please visit this page.