What does the introduction tell the reader about the narrator with regard to fulfilling the reader's expectations for an autobiography?

Normally in a autobiography text such as David's Cooperfield, an introduction tells the reader about the narrators specific details of it's life such as the birth place and so on. In this case, the narrator tries to play with the readers expectations, and invites them not to expect a common autobiography.

Explanation:

In this case the narrator, tryes to catch the readers attention by expressing as if he was forced to tell his story, as if he didn't acctually want to tell it. The narrators writting would be less formal, it would not follow the literary standars of an autobiography.