FACT: 30 to 60% of visitors tend to drop off and click to another site when they are forced to click their mouse more often than necessary.FACT: People who use internet are usually those who are always on-the-go and don’t want to spend time figuring out how to navigate any web site.
FACT: It takes all of ten seconds for most first-time visitors to spend time on any web site before deciding if it's worth any attention.
Yes, it only takes ten seconds for viewers to get interested and stay a little longer to know more about your site and get information they're looking for.
This is main reason why first page is most important in any web site. Rule of thumb is to have a page that is direct to point, doesn't waste time, and doesn't waste bandwidth. It's necessary that you get to crux of your message and do it quick. Or else your audiences are outta here.
Studies prove that human nature cause to lose focus on whatever it is that we are paying attention to after initial ten seconds. The mind seem to think that after ten seconds, either object of attention gets better and interesting, or attraction just fades because of too many things.
And ten seconds is important in any web designer's job. A designer has to remember that in ten seconds, web page should be able to deliver something useful, if not everything.