When there is nothing left to do. Nothing piled up, no ideas that you want to implement, nothing that seems to warrant an improvement. As long as there is nothing left on the shelf and you have no intention of filling it up with things to do, it is time to quit. Pack up and move on to something else. Some other shelf you want to fill.
Some people ask me how I quit a nice, secure, cushy bank job for the uncertain life of a writer. My shelf there at the bank was bare when I left and I somehow felt like I did not want to fill it again. I left it bare, took as much meaning it gave me from all the years and the experience, and left. That was about all it needed to let it go.
When I look at my writing career today, I wonder how my shelf looks. It looks so full that I wonder sometimes if I have the time to put them all down as stories. It is a wonderful place to be in, when the shelf is full. Ideas, undeveloped themes, uncharted territories, ah, this is wonderful. Novels, short stories, scripts and so much more.
The same goes for my book shelf which is pregnant with unread books, all that I picked with great love and interest over the years. So many more books to be reread also and seen from today's perspective. On the movies list also there are so many lying in the waiting-on-the-shelf list, many from Sagar's enviable collection. And many to be rewatched again! And there is so much music to be rearranged, listened to, friends to be called over and shared with.
Ah, life is full and content. There is much to look forward to!