That's not always easy, though.
"It's tough. It really is," he tells Welch when she asks whether he has decompressed from his Super Bowl win in February. "Because once the season's over you're already just a few weeks away from the Indianapolis Combine. You're another week away from free agency."
The football season doesn't seem to end for Belichick. "Now we're into the spring workouts, the draft, and then once the draft's over our players come in," he says.
Belichick knows that if the team isn't training early, it could come back to haunt them. "If you don't work at your team now in the spring," he tells Welch, "you're probably gonna pay for it in November. We just gotta keep grinding away."
That's the kind of laser focus it takes to become a master of your field. Belichick doesn't dwell on the past. He concentrates on what the team can do in the present. "We're on to 2017," he says. "Nobody cares about 2016 anymore."