The same is true of closing a project. The excitement of getting it done has probably worn off and maybe the subject matter – and even some of the people – are wearing you out. You’re anxious to move on to the next thing.
But, don’t give in to the temptation to put things away half done or disorganized. Clearly label and file the documents, electronically and paper if applicable. Make sure they will be easy to get to and use if they are needed again.