Comment by stevenh

Teams are spontaneously disbanded and their projects are moved to other countries because it prevents people who share the same allegiance or ideology that runs counter to Google's from conspiring to hide "accidental" exploitable bugs in the code which could later be used to damage the company. The project gets audited by the next team's fresh eyes and if an exploit is found then it is patched and can be traced back to the moles who can then be monitored or fired. Rinse and repeat until launch.