The change is a substantial shift for Facebook, which has traditionally encouraged people to publicly share posts, videos and photos.
Executives at Facebook who had run the various services were concerned that knitting together the apps would take a toll on the popularity and growth of their individual products, said the people, who were not authorized to speak publicly. And with Mr. Zuckerberg exerting more control, the executives were also fearful of losing autonomy and power.
Now, Mr. Zuckerberg is barreling ahead with his shift to focus Facebook on private messaging and away from public broadcasting, even if it means shedding some of his top lieutenants.
The departures add to the executive turnover at Facebook, which for years had been stable in its top ranks. Mr. Zuckerberg kept close many key executives, including his chief operating officer, Sheryl Sandberg, as well as Mr. Cox and others.