Final answer:
It is true that one should not wax over large or curved areas in a single go; doing one side at a time or separating the top and bottom ensures effective and less painful waxing.
Step-by-step explanation:
The statement that you should never wax over curves and should do one side of an area at a time or the top and bottom separately can be considered true. This is because when waxing, especially with hard wax, the application and removal need to align with the body's natural contours. By breaking the process into smaller sections, you ensure that the wax adheres properly and can be removed more effectively and with less discomfort. Applying wax over large or curved areas in one go can lead to uneven application, which can not only be ineffective but also increase the likelihood of pain or skin irritation.