"You've had people plowing into this market," said Nicholas Colas, ConvergEx Group chief market strategist. "And nothing makes you take your foot off the accelerator like seeing an accident."
Stocks plunge on economic news, oil price swings →
Nicholas Colas, ConvergEx Group chief market strategist, said blaming the health care ruling for the market's losses was "a convenient excuse."
Stock market cuts losses with late comeback →