One reason for the novel's title might be in Helga's condition in the world. The idea of quicksand is a state of being where one is sinking, being permanently drawn into an unknown point and extraction seems to only worsen the condition. On the surface, quicksand appears to be intact. Yet, with only a small amount of pressure, it gives way.
Both articulations of the quicksand concept can apply to Helga. On one hand, Helga appears very composed. She is intelligent, by all accounts, beautiful, and insightful about the world. She holds a global and local perspective about being in the world. In a superficial view, Helga seems to "have it together." However, in each of the conditions in her narrative, the slightest condition of pressure causes her to capitulate into a being of perpetual dissatisfaction. As soon as "the storm clouds begin together," Helga is immersed in a condition of self- doubt, unhappiness, and eventual escape. This consciousness is one in which psychological "quicksand" results, causing her to never find the happiness for which she yearns.
In another light, Helga's unhappiness has a quicksand quality to it. There is really no end point to it, as it keeps progressing downward as it drags her along with it. The ending to the narrative in which Helga is pregnant with another child and recognizes that escape from Alabama, unilke Naxos, Chicago, Harlem and Denmark, is not going to happen. She is dragged into an unknown condition. Any extraction is futile, only increasing depression as it is a reflection of failure. Like quicksand, the only known is that where she is going is not good. Helga's characterization is where much of the quicksand concept is evident, making the title quite fitting.