The goal of any NFL team is to build a sustained contender that gives you the most chances to win a Super Bowl championship (or multiple championships). Teams build their rosters with the intention of prolonging their windows, and with enough chances, you eventually will have the right bounces to get over the top.
However, the NFL builds competitive balance checks to ensure that keeping a window open is as difficult as possible. Mechanisms like the salary cap and reverse draft ordering limit teams’ abilities to keep their windows open for as long as they would desire.
Reverse draft ordering is the most effective way of achieving competitive balance.