GFT UK How do low volumes affect spread trading? David Morrison, Market Strategist at GFT UK comments. Trading small caps. Low volumes generally mean that the market is trading thinly. If you are looking at small caps these generally often trade at low volumes. These offer incredible opportunities but they also have to be treated with caution - because they are not mainstream stocks, fund managers don't get involved so they don't get so much interest. Low volumes are particularly dangerous in a falling market.