Perhaps it's an egg. Having been driven to the site by a search engine, you begin to mouse-over the white page and the egg to see what's hidden. Not very effective marketing, unless the site is the billboard for a design shop seeking to intrigue visiting designers. Contrast that with the homepage of a very complex company like General Electric. There, the multiple doorways to the numerous topics of a giant multinational company are easily found on the homepage.
Homepage navigation is important but so is homepage marketing.
And that's not always possible to do effectively with a hard sell. Hospitals, for example, seeking to attract return visitors to their sites can make return visits compelling if the homepage offers frequently updated content on issues of interest to their visitors. Naturally, it's not realistic to offer medical advice. However, sources for updated medical news do exist and a number of them are free for web managers to use. The ultimate goal is to sell something.