Overview

Business rules can run twice when the 'Execute function' checkbox is checked.

Subject

When the 'Execute function' (execute_function) checkbox is checked, the business rule script will have an "immediate" function declaration, for example: 

function onAfter(current, previous) { 
} 
or 
function onBefore(current, previous) { 
} 

This function will get added to the script that will be evaluated. However, if there is a script in the BR script field which includes the function as well, it will get added to script that goes through the evaluation twice. 

The 'Execute function' is a legacy field and ServiceNow does not recommend having it checked on business rules.

Additional Information

The 'Execute function' is a legacy field and ServiceNow does not recommend having it checked on business rules.