RIM owned mobile, Apple was derided when arriving late into a non-sequitur field, and Google - how did an ad-targeting search engine become a major OS competito

RIM owned mobile, Apple was derided when arriving late into a non-sequitur field, and Google - how did an ad-targeting search engine become a major OS competitor? We've seen amazing churn in tech of late. If MS has been paying attention, they could pull it off. (Then again, there's Zune and Kin.)