Checking someone’s voicemail without their knowledge or consent is unethical, illegal, and an invasion of privacy. Voicemail messages are private communications intended solely for the recipient, and accessing them without permission is a violation of trust and the law. Attempting to retrieve voicemail messages without authorization could result in legal consequences, including criminal charges.
If you have a legitimate need to access someone’s voicemail, you should always obtain their consent first. If they agree, they can provide you with the necessary passcode or login information to access their voicemail.