Final answer:
The major disadvantage of oral communication is the potential for miscommunication, where the message can be unintentionally or intentionally altered, leading to a distortion of the original content.
Step-by-step explanation:
One of the major disadvantages of oral communication is that it can be prone to miscommunication. This happens when people unintentionally or intentionally alter the message and meaning during the conversation. Unlike written communication, which has permanence and can be reviewed for accuracy, oral conversations can change as they are passed along, leading to a distortion of the original message. It is different from having the advantage that in an oral communication people can ask for immediate feedback, which is not generally a disadvantage of oral communication.