Why?

[Justuas]

Is there any good reason not to join a pt while doing FATEs?

[Malzian]

Is there any good reason not to join a pt while doing FATEs?

Sometimes as a DPS while leveling I would queue for a dungeon and run FATEs while waiting (sometimes up to an hour). If you joined a party for a FATE you would lose your spot in queue, so sometimes there's a reason. For FATEs like Ixion, however, you really should join a party but sometimes it's difficult to get yourself noticed in the "inv plz" spam.