What is the value of the number field of the object that is obtained from Trigger.old? The initial value for a number field on a record is 1. A user updated the value of the number field to 10. This action invokes a workflow field update, which changes the value of the number field to 11. After the workflow field update, an update trigger fires.
Trigger.oldcontains a version of the objects before the specific update that fired the trigger. However, there is an exception. When a record is updated and subsequently triggers a workflow rule field update,Trigger.oldin the last update trigger won’t contain the version of the object immediately prior to the workflow update, but the object before the initial update was made. For example, suppose an existing record has a number field with an initial value of 1. A user updates this field to 10, and a workflow rule field update fires and increments it to 11. In the update trigger that fires after the workflow field update, the field value of the object obtained fromTrigger.oldis the original value of 1, rather than 10, as would typically be the case.