Why disable/delete Guest Accounts?

Disabling or deleting  Guest accounts is a good step to improve cybersecurity because it helps to prevent anonymous and unauthorized access to your Microsoft 365 tenant / domain. Guest accounts are typically intended for temporary use by visitors or other non-regular users, but they can also be used by malicious actors to gain access to a system. Disabling or deleting these accounts, makes it more difficult for attackers to gain access and can help to reduce the risk of a security breach. Additionally, removing guest accounts that are not needed can also reduce the attack surface of the system and make it harder for attackers to find vulnerabilities to exploit.