Different sports, Hockey is more like Baseball, where you draft 18 year olds, most of whom have long odds of ever making it, then wait five years to find out if you were a genius or dunce. Only a few at the top of the draft will become stars and make the majors on a shorter timetable. So you have to think "Soviet," five year plans where you work around a salary cap (while baseball has a soft cap, it's become much harder in recent years).
In the NFL, contracts aren't guaranteed, injuries are frequent, and rosters are constantly churning. While the majority of starters come out of the top three rounds, you need the later round picks, UDFAs and street free agents to rebuild your team. Three years is the long-term in the NFL.