Curiosity causes both characters to regret decisions. The dad wishes with the paw and it kills his son. Pandora opens the box and released bad things. This causes both of them to regret their actions.
Curiosity causes bad things to happen to both characters in both stories. In "Pandora's Box", she releases things that cause evil in the world. In "The Monkey's Paw", the fathers curiosity to wish cause the death of his son.
Don't let him in!!!
Both story put the objects in different places. Pandora hides the box under the bed so curiosity didn't affect her as much. The Dad puts it the monkey paw out in the open.
In both stories, they both end up with bad things happening. But, in "Pandora's Box", they get hope out of the whole ordeal. In "The Monkey's Paw", the only thing that happens is the death of the father's son