Facebook is losing its marketing boss at an inopportune time for its brand.

Facebook CMO Gary Briggs is retiring more than four years after leaving Google to join the company, he announced on Tuesday. In addition to traveling and working with other companies as an advisor or board member, “I plan to help the Democratic Party on some efforts leading up to the US midterms this year through to 2020,” Briggs wrote in a Facebook post (embedded in full below).

Prior to joining Facebook in August 2013, Briggs served as Google’s VP of consumer marketing before being appointed Motorola Mobility’s CMO following Google’s acquisition of the hardware maker. He had previously worked at eBay and PepsiCo.

During his time atop Facebook’s marketing organization, Briggs oversaw the company’s continued investment in TV advertising with its cross-platform campaign to promote Facebook Live in 2016, which followed the company’s initial foray into TV advertising in 2012. Most recently, Facebook debuted a campaign called “Hopes” in an effort to promote positivity and associate Facebook with optimism.

Optimism is what Briggs’s yet-unnamed replacement may need. While a majority of people have a positive view of Facebook, according to various brand favorability surveys, the lens through which people look at the company isn’t as rosy as it once was. Last year, as criticism of Facebook’s role in spreading fake news meant to undermine the 2016 US presidential election rose, Facebook’s ranking in YouGov’s BrandIndex — a measurement of brand health — fell out of the top 10 brands in the US. Internationally, people’s feelings toward Facebook may shift later this year, when the European Union’s General Data Protection Regulation (GDPR) takes effect with the potential to make people across the continent and beyond more aware of the information Facebook collects about them and how the company uses it.

At the same time Facebook’s new CMO may be pressed to protect its brand here and abroad, the incoming marketing chief may also be compelled to promote its product, which is undergoing somewhat seismic changes. For starters, Facebook’s recent push into TV-style original programming through its Watch tab may require its own push to attract TV audiences through a TV campaign. And more recently, Facebook has acknowledged that social networks like its own can depress people. The company has responded by planning to reorient people’s News Feeds away from passive, public content like news articles and short videos in favor of content that elicits discussion among friends and family members, but to succeed in that shift, Facebook may need to reinforce its new “time well spent” mantra through marketing.

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