A burn-in test is generally run at the manufacturer’s premises before the machine is shipped, or after a repair has been carried out in the workshop or repair centre. It is carried out to weed out the machines or components that will be early failures. If a machine or component is going to fail it will do so in the first 10 minutes of its life. It is also available on the manufacturers or the third party diagnostic disks. It is a test where the diagnostic routines are run over and over again. It may be all the routines to test all areas of a machine, or just one test to thoroughly test one item - a hard disc for example.