The purpose of a lockout tagout checklist is to

Employees who work with hazardous energy must be trained in energy control procedures, also known as Lockout/Tagout. Measures must be taken to disable machinery to prevent the release of hazardous energy during maintenance procedures.

The purpose of a LO/TO checklist is to make sure that any of the workers can find out who put a lock on something. A LO/TO is used to prevent any unwanted use of machinery or to prevent any cabinets that contain hazardous chemicals to be used or opened. These things are very useful in any shop environment where there are many dangerous things around you.