Lithops are succulents that store water in their leaves, and they are very sensitive to overwatering. When lithops are overwatered, the leaves will start to rot and the plant will die. The best way to prevent this from happening is to water your lithops only when the soil is dry. If you think your lithops are overwatered, take a look at the leaves. If they are soft or mushy, it's a sure sign of too much water. Another way to tell if your lithops are overwatered is by looking at the color of the leaves. If they are turning yellow or brown, it's a sign that the plant is not getting enough sunlight. If you see any of these signs, stop watering your lithops and let the plant dry out completely before watering again.