Most deserts have rainfall patterns that come only two or three times a year, and then it comes VERY intensely.
Thunderstorms give rains to the desert, and they only rain in parts of a very large expanse of land.
The most important factor for life to bloom in the desert is to have the rain soak quickly and deeply into the ground so that it will not evaporate as soon as the sun comes out after the storm. When the water is in the soil, it may then come back out on the surface in springs, keeping the soil wet most of the year. In Nevada, in the Great Basin of the United States, most of the springs have dried up after the essential life that helped the water soak into the soil was disrupted by humans. They did not understand how the many species worked together to help the desert bloom. We are now beginning to learn how important the many species are and to understand better how they work together.