Happened once for me and in my case looked like she did't wipe it at all
Poor you. It happened once to my daughter and she's a very confident person but she didn't say anything because she didn't want to upset the client - and you would be wouldn't you, if you were that client?
Luckily this is quite rare. We give our clients an aloe Vera wipe and tell them to use it everywhere they have hair, front and back to "hydrate the skin and avoid the wax gripping too enthusiastically" most clients are keen to use it once they know it's in their best interests. Some girls are a bit baffled though, so we write notes to explain better next time "especially in the most delicate, intimate folds of the skin - that's where it's needed most"