This process of writing of job costs in Sybiz Vision is used when costs have come in after the final invoice has been generated for a job.
Even though the job has been invoiced to the customer, you still want to record the costs against the job to get a true picture of the profitability of the job.
Once you have allocated these costs, in order to close off the job, you need to write off these residual costs in order to zero out work in progress.
This video demonstrates how to write off those residual costs in the Sybiz Vision Job Costing module.