Ask HN: What companies succeeded/failed in morphing from product to ecosystem?

To clarify, the question centers on a common challenge for successful startups: how do you transition from a single product -- the product for which you're known for -- into a company with multiple viable, related products (e.g., bundle/ecosystem) serving the same user? For instance, Google Docs serves the knowledge worker but Google Cloud does not, so while these are two successful products, they would not form an ecosystem/bundle in this definition. Square is attempting this transformation from a payment provider to a whole solution for small businesses. Dropbox is attempting to morph from file-sharing into a collaboration platform for knowledge workers. Groupon is attempting to morph from daily deals into a site for saving consumers money. 1) Which companies are the best role models for how to transform into a multi-product company? 2) Why did these companies succeed where others did not? 3) Which companies offer the best cautionary tales?