Painting frescos is hard and dangerous work. You work on a scaffolding, high up in the air. It’s easy to forget what you are doing, it’s easy to fall. Michelangelo fell when he was painting the wall of the Sistine Chapel and hurt himself so seriously he was out for weeks. He was alone in the chapel when it happened and he dragged himself home like an injured cat. There he lay in great pain for several days until a doctor came and helped him recover. The Spanish painter Murillo died from the injuries he got from a fall off the scaffolding in a Seville convent.
Humorous sketch of himself painting the Sistine Chapel ceiling, by Michelangelo a public domain photo here
He was 30 years older when he painted the Sistine Wall and, perhaps from feebleness, lost his balance or slipped on the scaffolding.