Should your glasses come out with a damaging rainbow pattern the probable cause is the water was too hot, try using cooler cycles. You can also purchase a glass ware protector to add to the dishwasher to protect delicate glass, some 'all in one' tablets have this ingredient added to them, which helps prevent damage to your glasses. It may be worth checking that your glass ware is suitable for the dishwasher, damage is unfortunately not reversible here are some examples:

examples of marks left : on the far left are rainbow colour marks - use a glass protector to prevent damage to delicate glassware