Twitter, Tumblr, and Reddit

Frank, can you put in writing here 2 lists for each of these three platforms as to what they did right vs what they did wrong?

They obviously were mostly right since they are successful.

https://en.wikipedia.org/wiki/List_of_most_popular_websites

Twitter and Reddit were first to be social in their niche.  Tumblr added theming to social blogs.

closing