A read-only default lets a user or automated system view data while preventing changes unless write access is explicitly granted. It applies the principle of least privilege: start with only the access needed, then add narrowly scoped permissions when a task requires them.
In cyber security, this reduces the damage caused by compromised accounts, mistaken actions, or AI workflows influenced by untrusted content. For example, an AI assistant connected to email or business records can begin with permission to read, while updates require separate authorization or human approval. If writing is needed, limit it to specific records or fields, log changes, and consider rate limits. Read-only access does not prevent data exposure, but it helps protect data integrity and keeps automation from making unauthorized changes.