They are just indicating how it can be used in a place with no prior installation facilities. Nobody would buy a desktop dishwasher if they had the space/installation to put a normal one.
Xiaomi has revealed the Mijia Smart Desktop Dishwasher S1, which is now available to pre-order in China. The gadget has an AI smart wash, assessing the dirtiness of your dishes and optimizing the water level accordingly. The compact device takes up around 0.19 m² (~2.05 ft²) of space on your countertop and can wash up to 39 items simultaneously.