Why will I be resigning as Incorporator?

A company’s incorporator has a single role at the very beginning of a company's life: to file the incorporation papers with the State of Delaware, adopt the bylaws, then hand the company as an empty shell to its new Board of Directors. 

The distinction between the role of the Incorporator and ongoing Board is made by Delaware law, which would permit these to be different individuals or groups. To keep things fast and simple, you will wear both hats, first as incorporator, and next as the first member of the Board.