A deficiency, or shortage, occurs when there is an insufficient amount of a resource, product, or service to meet demand. This can happen in various contexts, such as food, water, or essential goods. For example, a food deficiency may arise during a natural disaster, leading to a lack of available supplies for affected communities. Deficiencies can also occur in economic terms, where the supply of a good does not meet consumer needs. This can lead to increased prices and competition for the limited resources. Addressing a shortage often requires intervention, such as government assistance or changes in production methods.