Sometimes it's so easy to know and other times, arg! At first I thought I would be doing the whole painting in colour but it being primarily black and white seems to fit with memento mori.
When my husband saw the rose he said it looks like a dead rose. "it is!", I exclaimed with joy. So I'm glad I was able to convey that. My challenge now seems to be how much more colour do I put in it, or to leave it alone and just tweak it here and there. This is a conundrum many face, but one I enjoy.
Found a great example of how an artist several years later decided a painting needed to be finished. While the difference may seem subtle, it nevertheless has improved it.