Despite it being a obvious money grab, I also like to think the weekly lockouts/caps also serve as a collective "enrage" for the whole player base. Think about it. Another week, another piece of Gordian/ Antiquated gear. As time passes by, content gradually becomes "easier". Eventually, it gets to a point where, even if a player plays their class to the bare minimum, they can clear content due to being over geared.

I know I'm not the first to describe this phenomenon, but I think this magic point should be called, "The Player Enrage Timer".