How ironic that a sailor about whom little is known should be named Frank, a name that implies honesty. Yet, his character is ambiguous. As Eveline sits at the window the night before she is to leave with him, she contemplates her future. Eveline's perception of Frank is romantic--He treats her to the opera, music, singing; he is "kind and open-hearted and manly." Like a knight in shining armor, his face is described as "bronze."
Along with her romantic perception of Frank, there is a suggestion of exile as opposed to freedom as Eveline recalls his tales of distant countries and the remote seas he has sailed, having started as a deck boy. As an itinerant sailor for years, it is dubious that Frank will settle down in one place with one woman. This is what Eveline's father believes about Frank: "I know these sailor chaps."
The ambiguity about Frank's appearance and true nature is what contributes to Eveline's indecision. As "her time was running out," she remembers the promise to her mother to care for the children. As she stands, Eveline thinks, "Frank would save her. He would give her life, perhaps love, too." She repeats this as though unconvinced.
In the end, Eveline does not have enough faith in Frank to go with him. She remains, paralyzed at the idea of trusting him; she worries that he "would drown her," and "amid the seas she sent a cry of anguish! Frank is not real enough for her to believe in. She remains, "passive, like a helpless animal," trapped in the abusive life under her father because she is just not certain enough about Frank.