I keep getting asked, "What's wrong with the stock market? Why are we off to such a weak start?"
I'm not sure there is anything wrong with the stock market. The biggest problem with the stock market is that participants think there's something wrong if stocks don't go up every day!
The most likely reason for the action is that the market was jammed higher every day for at least two weeks at the end of the year and we need to consolidate.
(Read more: This week may decide where stocks close out 2014)
Still not satisfied? I get plenty of other opinions thrown at me, much of it unsolicited, to explain the weakness:
1) Markets are beginning to price in slowdown in QE;
2) Reallocation: funds that have fixed percentage allocations to bonds v stocks may still be in the process of selling equities to buy bonds given outperformance of stocks last year.
3) China data has been weaker, hurting emerging markets
4) U.S. economic data has been choppy in the new year (ISM Services, December Auto Sales, Retail Sales)
5) Cold weather has impacted the economy. Our Phil Lebeau has pointed out that storm cancellations will cost airlines lots of last minute bookings, which are the most profitable bookings.
One thing for sure: no big bets are being made in the markets, at least not yet. Volume, even today, has been anemic. Today is arguably the first day when much of Wall Street is back, yet consolidated volume at the NYSE still looks slightly below an average day.
(Read more: New year starts off with a whimper)
—By CNBC's Bob Pisani