1.- Google had - and still has - a simple, clean, clear, minimalistic user interface. no frills, just the logo and the search box - easy and fast to load. And this was a key feature with the slow internet connections of the early years 1999 -2001 - while Yahoo and most of the other search engines were more like generalistic portals, full of confusion, full of useless features and useless links, full of annoying banner ads, heavy and slow to load.
Google had a clear understanding on psychology of perception, and how the interaction eye/brain works, while the bigger competitors didn't.
Bottom line is: If the user visits a search engine, what he wants to get is simply that: just a search engine.
A search engine which is fast and reliable. If the user wants a generalistic portal, he goes to a portal, not to a search engine. Larry Page and Sergey Brin, the Google Executives, understood this, and this was what they delivered. And made their users happy.
2.- Google had - and has - reliable search results (not always, but most of the time). Page and Brin's PageRank algorithm worked well.
3.- Google got good advice from VC's and from Wilson Sonsini Goodrich & Rosati. Larry Page and Sergey Brin have been advised and assisted since the beginning by John Doerr, VC Partner of Kleiner Perkins and by Wilson Sonsini Goodrich & Rosati, the leading law firm of Silicon Valley.
Insight on Google Business Model
4.- Google introduced a smart, innovative and quite risky business model - Adwords - and the pay per click concept. The risk proved winning, and the innovative business model worked. Still today Adwords is the main source of revenues of Google Inc.
5.- In the following years, Google became a powerhouse with an impressive pipeline of new great products - Google Maps, Google Earth, Google Video, Gmail. And slim revenues.
6.- Google worked very hard on Brand Building. It seems that brand...