what is a key factor in the governess's agreement to take the position at Bly?

In the story Miss Giddens, a governess agrees to take a position at the estates of Bly. The position requires taking care of two young children, the advertisement having been posted by the uncle, who asks not to be disturbed, even under the most serious of circumstances. The governess meets with her master only twice, but these two occasions seem to have a tremendous effect upon her emotions. Apparently, she becomes attracted to her employer, even to the extent of being infatuated by him. She thinks of him constantly, but adheres to his request not to be disturbed even when she feels things are getting out of control.

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At 20, she's swept off her feet by a man she barely knows, but one that she immediately has a crush on....... after meeting her future employer she romantically takes the position as governess; her reason....... very much a romantic one.

We also have to consider the fact that as the daughter of a parson (a poor parson), this kind of opportunity may not present itself again; so, off she goes!