Nellie Mandle worked as a machine operator. She had been told on numerous occasions that if her press ever jammed up, she was not to stick her hand in to unjam it; rather, she was to use a special safety fork with a long handle that would allow her to unjam the machine without inserting any part of her hand into the press. Her machine jammed, and she looked around for the safety fork. Realizing that the worker on the previous shift must have removed the fork, she reached her hand inside the machine to unjam it. Before she could remove her hand, the machine cycled, catching her hand and injuring it severely. She filed a worker's compensation claim, which her employer contested because she caused the injury by her disobedience of the safety rules. Evaluate the employer's argument.