Back in 2004, MA Fleury spent time with the Penguins AHL-affiliate Wilkes-Barrie Penguins. The linked video below is from a game he elected to wear a helmet-cam so people could get a sense of what the goalie sees in a game.
For goalies, particularly young ones, watching this reinforces the need to watch the puck from point of shooter’s release all the way into the save. Many goalies of all ages do not visually follow the puck after the release of the shot but it is of the utmost importance.
Why? Obviously it helps with correct save movement. More importantly, it allows the goalie to better redirct a rebound if the shot is not able to be controlled at the body. Additionally, watching the puck into the save eliminates surprises and helps the goalie better prepare to face any rebound.