When I very first started, I just wanted a sub job. XD
Then I wanted to get to 30 so I could take up an advanced job (SMN)
Then I wanted level 20 so I could solo the avatars.
Once I did that, I leveled 3 more levels and decided, my real goal was Fenrir. I had thoughts about just saving gil to leech him, but ultimately decided I'd level another job to do it myself.
I've leveled BLM to 60 so far, so I can start working on the avatar whispers soon.
And then, Fenrir... he is my current goal, and almost one I've had from the start (as I had been interested in SMN since I looked at the back of the box and saw Ifrit)
Once I get him, I'm going back to level SMN mostly, to 75.
Never expected to take this route when I started as a WHM XD