from the vector X we need to run the model again and these n different times that we run the model cannot be parallelized each of these operations of sampling another X is dependent on all of the earlier X I values and that means that there's really no choice but to schedule them one after another regardless of how much bandwidth we have available one other smaller drawback is that the generation process is not guided by a latent code many of the other models that we study have a latent code that we can sample first that