The difference is the defense in front of the goalie. If you see offensive players camped out in front of the net hacking away at rebounds and tipping and screening shots that are blasted at the goalie, the goalie has very little chance to do anything.
Pitchers in baseball also need to rely on a good defense. A ground ball pitcher needs sure handed infielders with good range. If so he will get rally killing double plays. Although pitchers are often assessed on how difficult it is to make contact against them, some pitchers will pitch to contact or else draw soft contact ahd there are statistical models that enable them to be assessed in these respects.
These are team sports and position players rely on good performances by their teammates to succeed.
From what I have seen I think the Pittsburgh Penguins have a very strong chance to repeat.