All deserts receive less than 10 inches (250 mm) of rainfall on average per year. Some receive virtually no rainfall for decades or even centuries.
A waterhole is a pit in the ground usually in deserts, that is filled up with rainwater.
No, deserts or parts of deserts can be several thousand feet in elevation.
No. Height varies widely. There is even a formal division between high deserts (above 2,000 ft) and low deserts.
Clouds do not precipitate in deserts primarily due to low humidity. Deserts have very dry air with low moisture content, which limits the formation of rain clouds. The low humidity prevents sufficient condensation of water vapor in the atmosphere to form clouds that can produce precipitation.
Your question is redundant. All deserts are classified as deserts because of the low precipitation.
There are both cold deserts as well as hot deserts.
Some deserts have low elevation, some have a rather high elevation. Not all deserts have a low altitude.
Nighttime
low moisture.
Deserts have little rainfall. However, if the desert is irrigated, it can be, and is, quite porductive.
The only thing all deserts have in common is low rainfall.
Deserts are typically dry and have low humidity levels, making them arid environments.