farlinzee

It is a complicated question. The quality of the materials and craftsmanship influence but so do accidents of the kiln.

Ultimately you must be prepared to trust your instinct as to which is a fine pot and which is not.
example:
Japanese collectors greatly value simple peasant made pinch pots from Korea because of their unpretentios beauty.

If you go to Yixing and request the finest pots you should expect to pay a premium.

If you seek affordable pots you may well be shown the finer pots at a notably lower price.

For quality of workmanship look to the feet and bottom of the pot.

Cheers
Lindsay