Cutting double hinges in a food can lid prevents cut fingers

My mother would always cut open a food can to have two small hinges on the top lid.  That way, she could push down the top lid at the back, between the two hinges, and then lift up on the front.

The top lid stays on the can and does not fall into the food below.  She told me that keeping the lid on the can prevents cut fingers that could happen by handling a loose lid that been separated from the can.