What would you think about copying ideas for commerce?

What is up with tech companies copying one another and doing better than the copied company?

• If you see recent history, Apple copied from Xerox and then did better than them in that vertical. Then Microsoft copied from Apple and were a greater success (in the OS / PC  space atleast). And in the more recent years, Facebook was allegedly copied and extended from the HarvardConnection idea. What do you think is happening here? Basically, what I would like some ideas on is what people think motivates the copying company to take the idea and then later make them more successful?

• Answer:

  It is hard to start a category.  As the first mover into the market you need to not only invent the item, but market why it is important why everyone should use your product.  Often entering a market later gives you a chance to create a more compelling product. You forget that Friendster was the first big social network, the problem was that no one knew what to do after they added their friends.