Resin will absorb water from the air in a shop that does not have good HVAC control of temp and humidity.

As the reaction of the resin generates heat, the moisture is driven off and that can cause warping.

Also if a part is pulled from the mold too early before everything crosslinks, that can cause warping as well.

That is a common issue with bodies that have thin sections which do not generate sufficient heat for a full chemical reaction cure.

Can't speak to the plastics used in 3D printing, but I would imagine there are similar concerns with curing of the part.