What do people mean when they say a meeting could have been an email?

When people say a meeting could have been an email, they are stating that the information shared in the meeting did not substantiate the time taken for the meeting and the information could have just as easily been disseminated via email. This is a slang-type phrase used in the corporate world. People often use the phrase when they think that the time taken for the meeting was a waste or the information shared was basic and did not require heavy discussion.