What is a single point of failure?

A single point of failure is anything whose loss stops the whole operation, with no alternative path:

• One internet service - no second connection, so an outage at the exchange is an outage for you.
• One person - the only one who knows the supplier, the password, or the process.
• One device - the laptop that holds the only copy of something.
• One account - the email address that every other account’s recovery points at.

You cannot eliminate them all. Find the three that would hurt most and give each one a second path.