Investors are concerned that shares have gotten too expensive and there's no reason to buy into the market at these prices.

Investors are reassured zero interest rates will continue for some time, and given Japan's strengthening economic growth, companies stand to profit.

It seems everyone has been a bit too optimistic on shares.

Strong demand for digital consumer electronics such as flat panels and mobile phones is helping to make people optimistic about technology stocks.

The news on U.S. Steel has prompted some buying of steelmakers. You cannot completely rule out the possibility of takeovers of Japanese companies.

It's really difficult to buy technology shares without any real signs of a turnaround in prices, which everyone has been expecting for some time now.

It's a weak market like this, it's easy to take negative news to sell, such as with the banks today.

The yen doesn't look like it's going to strengthen anytime soon, which is a plus for exporters.

Profit-taking is continuing for bank stocks and others as we await earnings results. Without any reasons to buy and no direction identified, the market may drop further.

Earnings expectations have been a bit high and, given the disappointments in the U.S., those expectations have been toned down. That's going to help keep the market weak.