Always be prepared; if you’re going to meet the same people a few times, those are the people you should most be prepared for. In the NFL, divisional foes are the teams you build to fight against. It forms your identity, it defines a given arms-race. You’re not going anywhere if you can fend off your rivals.
The Detroit Lions have not posted a stellar record against NFC North foes in recent years, but with a new regime gearing towards the second year of a rebuild, the Lions are beginning to define themselves more and more.