My impression from working at Google is that people are similarly promoted based on implementing new features rather than maintaining existing features, including bug fixes. It's been 6 years now since I left, but I can still tell when there's a promo cycle because the UI on my Android apps change arbitrarily and become slightly buggier.

Just to rant about both companies, Amazon Prime's Chromecast support seems to be currently bugged out. It plays for a few seconds then gives up with a content not available error. Maybe it will work again in a year?