I think importance of owning UI/UX has been underestimated lately because importance of APIs and 3rd party ecosystem has been recognized. Especially in mobile s

I think importance of owning UI/UX has been underestimated lately because importance of APIs and 3rd party ecosystem has been recognized. Especially in mobile space, many investors seem to suggest that don't concentrate building UX, but outsource it to 3rd parties by creating good APIs. I'm not convinced that this is the right approach as UX really defines what your service is about. Twitter might be an outlier here, it's a rare startup that is succesfully operating mainly in protocol space. Many other successful services are owning their main UX. E.g. Facebook, Dropbox, Foursquare, 37signals products to name a few. They have APIs and it's clear that those provide real value, but core experience is still defined by their UIs. Now that we are starting to have open source or inexpensive scalable solutions for backend, developing good UX is actually becoming the hard part. If you outsource this hard work to 3rd parties without providing great financial opportunities for them, you are actually not providing value .