There are many ways to build NHL projections, be it with a statistical model, using the betting market as a guide, or something else. But one of the most important factors is building out NHL projections that can be measured against lines in the market. For example, many smart bettors are keenly aware of line movement and which sportsbooks post the best prices.
A lot of factors are considered by expert NHL bettors, both in terms of on-field performance and the betting market.