Glasses can come out of the dishwasher with a white, cloudy film that makes them look dirty even after a full wash cycle. The cause is usually hard water, detergent residue, or glass etching.
The important detail is that some cloudy marks can be removed, while others may be permanent.
If your water is rich in minerals, droplets can dry on the glass and leave a pale film. This type of cloudiness often looks worse when the dishwasher is overloaded or when rinse aid is missing.
Mineral film is usually the easiest problem to improve because it sits on the surface.
Using more detergent than needed does not always mean cleaner dishes. In soft water especially, excess detergent can leave residue and make glassware look dull.
Try using the recommended amount, and avoid packing glasses too tightly so water can rinse them properly.
If the glass has a rough, hazy look that does not improve after cleaning, it may be etched. Etching is tiny damage to the glass surface caused by heat, water chemistry, or repeated dishwasher cycles.
Once glass is etched, the cloudiness cannot be fully reversed. In that case, prevention is the best solution.
Use rinse aid, choose a gentler cycle when possible, avoid very high heat, and do not use more detergent than necessary. If hard water is a problem, dishwasher salt or a water softening setting may help if your machine supports it.
Cloudy dishwasher glasses are usually caused by mineral film, detergent residue, or permanent etching. Identifying the cause helps you know whether the marks can be cleaned or only prevented.