Compare Frankenstein with The Rime of the Ancient Mariner.

Mary Shelley herself, along with numerous critics, has
acknowledged her debt to Samuel Taylor Coleridge's "The Rime of the Ancient Mariner" in
her Frankenstein. Clearly, the epic of damnation and redemption
influenced the impressionable teenage author of a novel with a similar theme. But
another reason for the allusive presence of the poem in the novel can be summed up in
one word: admonition. Both "The Rime of the Ancient Mariner" - told by the hapless
seafarer to the captive audience of the Wedding Guest - and Frankenstein -
ensconced in the letters of Robert Walton - are told from the second person
point of view, the narrative of warning, prohibition and responsibility.
Frankenstein's second person narrative, and the many allusions to
"The Rime of the Ancient Mariner" is likely Mary Shelley's warning to the reader. But
about what is the warning? The answer can be found in the direct reference to
Coleridge's poem in the words of Robert Walton: he goes “to the land of mist and snow,”
yet he swears that he shall “kill no albatross” nor, says he, shall he return “as worn
and woeful as the ‘Ancient Mariner’”. His promise, like the grandiose quest of Victor
Frankenstein, is ironic. Both men are carried away by a hubristic search for knowledge.
It is only by listening to Frankenstein's cautionary tale about the cost of wresting the
secret of life from God that Walton is dissuaded from playing God with the lives of his
fellow-travelers. He turns back from his pursuit of personal glory, the fate of
the ancient marier ringing in his ears.