andr: One thing I think every Silicon Valley startup and investor should be afraid of is the incredible rate and depth of adoption of new technologies in China. I came across two examples recently. First, in China e-books have taken over paper books, not just in volume, but in publishers' minds [1]. Second, payment systems like AliPay are becoming the dominant in just a few years, completely circumventing credit cards [2]. Now, neither of these are technological breakthroughs in themselves. The Kindle has been around for over 10 years, and Apple Pay and its precursors are not news, either. However, neither of those technologies has had the impact on their respective markets that the creators hoped for. Paper books are still frequently cheaper than their Kindle versions, and there have hardly been any noteworthy straight-to-Kindle publications. Likewise, Apple Pay, which is only a replacement for your physical card, but still a transaction mostly owned by Visa/MasterCard, and not Apple, is still far from a dominant purchase mechanism, even in the Bay Area. All in all, the pace of adoption of disruptive technologies in the US is pretty poor. So, as an entrepreneur, I'd be much more worried not about inventing the cool new tech before China, but actually getting people hooked on it.