What do you think no site can succeed without? Is there really anything that all successful sites have in common no matter what niche they are in? Yes, there is. And, if you know what that is and ensure your site has it, you'll certainly join the league of successful businesses online. But if you don't have this you CAN'T succeed online. So please, cut the long introduction. I want to know what it is so I can have my own share of internet wealth.
Traffic and lots of it!
Do you want to make money with Google's AdSense? Then you need people to click on those ads -- That means you need traffic. Do you want to promote other people's product and make money as an affiliate marketer? Then you need traffic to have referrals. Do you want to sell your own products? You also need traffic.
Are you fighting for a cause? Are you trying to help raise funds for the poor? No matter how noble you cause is, you'll NOT succeed online if you do NOT have traffic.
Don't waste your money on flash and graphics. Yes, you need to build a professional site but save your money. Build something clean and simple -- Spend very little on site-building. You can always improve your site. Commit yourself to massive traffic generation.
And, lest I forget, don't go into frenzy and start buying traffic all over the place. You will fritter away your hard-earned dollars and be left worse than when you started.
Take time to buy good books, read them and understand what they teach. Learn and master the techniques one at a time. When you read and understand a technique, apply it immediately. That's the way to go if you want your site to be a huge success -- With massive highly targeted traffic.