Toothbrush b. eBook on Cooking c. Internet Explorer d. The prices were too high. They couldn't find what they wanted. Some of those questions were pretty difficult.
Persistence is the most important key to succeeding on the web.
The web just isn' t that old. Everyone is still learning. The number one key to succeeding online is testing everything you can possibly imagine. This takes persistence. Money may help as well, but for many large companies this just means wasting tons of money on two million dollar Superbowl ads.