Mostly I think the turnover stuff is pretty overblown, with certain exceptions like ME:A where the entire upper development team seemed to leave over the course of development. You actually want some turnover, as new people can bring fresh ideas ... you just don't want a ton of it. I've read several articles over the years about turnover management an annual turnover rate of around 10% is generally considered healthy for a company, though the exact percentages vary depending on the type of business it is. But assuming for a moment 10% is a baseline, for a company of 500 people, that means 50 employees a year, which would be around 4 a month, which is exactly what was reported here. The only position that gives me any pause is Mateusz Piaskiewicz as lead level designer. That's definitely an important role, but not an irreplaceable one. I definitely do not think the sky is falling.