<Purpose of the job system>
In FINAL FANTASY XIV, the core of the growth system is the Armoury System. It is a broad ranging "horizontal" system in which players can develop other classes and thereby strengthen and grow in their main class. In contrast to this, the new job system focuses on growing and strengthening the main character class.
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<Purpose of the job system>
In FINAL FANTASY XIV, the core of the growth system is the Armoury System. It is a broad ranging "horizontal" system in which players can develop other classes and thereby strengthen and grow in their main class and was something of an innovation in the MMO genre.

In contrast to this, the new job system focuses on growing and strengthening the main character class. It's based on the totally unoriginal and stale mechanic that has been the basis of character 'class' progression in most MMOs since the dawn of time.
Sadly, a very vocal minority of players can't understand 'new' and insisted on this game being turned to the same-old-same-old models on the last century.

RIP innovation.