The divisions are divided into NFL sections, conferences and conference. Discussions and divisions are the most crucial, with only a handful of games left during the normal season. To be eligible for playoffs, players attempt to be the top division in each division (or have the top or second-best record among other division players in the games they play).
There are many teams that have more success than, say, Dallas or Philadelphia makes sense since either of the two teams will be the winners of the division and progress into the playoffs. But you cannot be sure that each of teams with the top results will make it to the wild teams.
The system could be somewhat opaque during this time of year, particularly when departments are stuffed with many teams with boring reports However, everything is logical when you are on top of the details.