Why does VQGAN+CLIP produce much worse results than Dalle-mini?

Both models are using the vqgan\_imagenet\_f16\_16384 model. I'm not sure what Dalle-mini does differently, but the results it produces are so much better. VQGAN+CLIP produces results that don't have anything in focus, even if the prompt is just a single object. I'm not sure if this is because of the augmentation randomization (affine, sharpness, color jitter) or not.

For example, here are the results of both models' results on the prompt "an art deco car driving down the street":

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artificial clip dalle dalle-mini