It involves propagating desirable traits, and weaning out undesirable traits. While domestication began with species found in the wild, it eventually leads to the development of new species which exist only in domesticated form. Corn was domesticated by people native to the Americas. Certain First Nations peoples still get a high percentage of their diet from wild sources including goose, moose, caribou, seal, fish and plants because of they have maintained or reclaimed traditional practices, but on a global scale this is unusual. At the beginning of the twenty-first century there is very little we eat which comes from truly wild species, and, indeed, there would be little hope of supporting 6 billion people without large scale domestication and agriculture.
Food is generally of a standard quality.
You can have a good idea of how much food you will have for the winter. You can adjust the amount of food you grow to the number of people in the community. Agriculture requires careful tending of the plants or animals being raised. Disease or adverse weather may wipe out an entire crop or herd without warning. Certain farming practices, such as irrigation, fertilization or the grazing of herds, can adversely affect the land.