Nobody really enjoys using most of the Yahoo! branded apps or websites, so the company's future rests largely on the money it can make from advertising. For this reason and perhaps others, it's not a good sign that Yahoo! CEO Marissa Mayer showed up hours late to a client dinner because she was asleep.

The Wall Street Journal has the sleepy story, straight from the recent Cannes Lions media expo:

Last Tuesday evening, Interpublic Group arranged a private dinner at the swanky L'Oasis for Ms. Mayer to meet executives from marketers such as Mondelez International, brewer MillerCoors and Greek yogurt maker Chobani...But Ms. Mayer was nearly two hours late, and several dinner attendees including IPG Chief Executive Michael Roth ended up leaving before she arrived, people familiar with the matter said.

Ms. Mayer told some attendees that she had fallen asleep, some of the people said.

Dreaming of future startup acquisitions and photo shoots, presumably. Of course, these advertising execs, who had just finished a long day to going to open bars and sponsored beach parties in Cannes, were not pleased:

"It is another instance where she demonstrated that she doesn't understand the value of clients, ad revenue or agencies," griped one Journal source. Could this screwup cost Yahoo! the sweet, sweet proceeds of Chobani GIFs on Tumblr?

Photo: Getty