Parul's manager, James, told her not to share an e-mail with anyone because of its proprietary information, but another manager asked her to forward it to him, saying that James approved. Without asking for a written request, Parul forwarded the e-mail. When James found out, he said Parul was guilty of being insubordinate, refusing to believe her story. What was the disadvantage of the oral communication between Parul and the second manager?