NHL scouts have one primary tool at their disposal: their eyes. To evaluate a prospect, they observe and analyze. There are few, if any, metrics involved.
If these were corporations looking to acquire a multi-million dollar asset, it would be somewhat preposterous to do so without some kind of advanced statistical backing. But, for hockey clubs, the right kind of metrics don't seem to be readily available at this time.
One thing we can track is the traditional stats. But there is a sentiment that junior hockey stats are a bad indicator of how good a prospect a player will be. It's the same reason college basketball stats are a bad indicator of NBA success: Players are at different stages of development, and each has unique situations to deal with. And in fact, metrics really don't come consciously into play when evaluating a player.
But it doesn't have to be that way -- especially as we move forward with emerging technology.
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