I think the author is referring to a shareholder being able to quickly sell their shares, and likewise quickly buy shares, due to the high trading volume.
A lot of these otcs have such low volume they are hard to buy and hard to sell.
Years ago with cydy I remember putting out share orders within a penny of ask, and no sellers over the course of the trading day. The volume was very low in those days, and it was very illiquid.
Even if the ask was bid, it would immediately go up a penny.