Multiple cells can perform different functions. A single cell can only perform a limited number of functions, but a group of cells can work together to perform a wider range of tasks. For example, some cells can specialize in producing energy, while others can specialize in transporting materials or responding to stimuli.

Multiple cells can provide redundancy and backup. If one cell dies, the other cells can take over its functions. This redundancy helps to protect the organism from damage.

Multiple cells can communicate with each other. Cells can communicate with each other through a variety of mechanisms, including direct contact, chemical signaling, and electrical signaling. This communication allows cells to coordinate their activities and respond to changes in the environment.

Multiple cells can form complex structures. Cells can arrange themselves into complex structures, such as tissues, organs, and organisms. These structures allow organisms to perform a wide range of functions and to adapt to different environments.

In summary, multiple cells are better than one because they can perform different functions, provide redundancy and backup, communicate with each other, and form complex structures.