For many writers the hardest thing is the ending! Especially for the writers of fiction, be it Action, Horror, Fantasy , Suspense , Drama or Science Fiction. Quite often we get caught up in the creative aspect and start writing up a storm with characters, plots and genres.
The various scenes and situations flash in our imaginations while the characters interact and tell the stories from their own views. Then after all the drama, action, suspense and build up we are faced with the final scene.
This can either make or break the body of work. Everything has lead up to the conclusion and it needs to tie up all the loose ends. It needs to make the reader happy that they invested all that time in reading your work.
If you've done it correctly then the audience is entertained and you are acclaimed a success! So yes the hardest part is the Ending! The End!
Regards Mike (Aka Professor M!) ;D