I've long wondered why companies don't put their more experimental stuff under a different brand ("X by Google"-- no not that X), and promote them to full brand-name once they've gone reliable. Probably they want such experiments to get a boost from being associated with the better brand, and they figure the brand stain of stopping those experiments isn't so bad. But these things build up over time, and each individual product manager probably don't think they're the last straw...

Another thought is that Google comes from an era of much more experimental web. Now the Internet is a much more established market, and platform stability is more a premium. Google is having trouble transitioning from their wilder younger days (of just a few years ago) to a more reliable company.