Often times new rugs from the dealer or rugs that have been rolled or folded for storage may not return to their original intended shape when first laid (even over a pad). Many larger rugs have been barrel rolled - a method of folding and rolling to make them more compact for easier handling and delivery.
These folds are caused by the foundation yarns being stretched while folded or rolled. Although most will release over time, there are ways to accelerate this process. And wrinkles in an