Paul Farquhar
Legend
If we are being charitable, we could say he liked to experiment with new techniques and materials (with other people's money).Which is why the Last Supper faded so much so fast. The refectory specifically wanted him to do it, but he hated working in egg tempera because it dries so quickly and he worked at his own (very slow) pace. So he tried to do it with a mix of tempera and oil paints, which… I feel like should have been an obviously terrible idea, but that man would apparently do anything to avoid being rushed to finish his work.
And TLS is a big painting. It would take anyone ages using the equivalent of primary school poster paint.