The elusiveness of Dracula lends to the suspense and angst of the story. As the master of darkness, he hides in the shadows and cannot be approached, but he can appear of his own will at any moment. The anticipation of his presence is as bad or worse that the thing itself.
However, this 'stalling' technique in epistolary form has often been criticized as the weakness of the novel. Indeed, all the soul-searching and speculation over the struggle between good and evil today would seem obfuscaory, even obsolete. One must remember the social context under which Stoker wrote 'Dracula,' a provocative work in which he raised some serious questions concerning sexuality, particular for women.