The importance of standards
File transfers with 3D environments are far from cross compatible.
it is rare for an animation project to work perfectly strait out of the gate from one program to another.
this is an example of an animation export from poser 6 into blender.
as you can see the bone or Armatures are miss aligned and some are not even present.
Armatures/bones are easy to imagine as human bones. they allow animators to poser figures just by moving the bones. which cuts down on animation time.
today with motion capture the animation process has been accelerated even further. where you can record entire scenes with actors and export the movement to be matched up with the animated figures.