Shatter/Wax patties, what causes it?

I was curious if anyone can throw some knowledge at me.

Sometimes during purging about 75% done some areas start to crumble up while areas directly adjacent to it are clear and hard shatter.

It doesn't always happen and happens in different spots when it does. (Thought it might be hot spots in the chamber)

A couple things affect the rate of waxing and those are points of nucleation and water.

The wax crystals are oil hydrates formed around a point of nucleation. The point of nucleation can be a particle of plant wax or a spec of plant material, so reducing the amount of wax by subzero extraction to avoid extracting it in the first place, better filtration, and attention to water sources, will reduce their frequency.

I do get condensation in the dish, thanks for the info!