The main advantage of purposive sampling is that a researcher can reach a targeted sample quickly. It is easy to get a sample of subjects with specific characteristics. Additionally, researchers are able to draw on a wide range of qualitative research designs.
Purposive sampling saves time, money and effort. It is flexible and meets multiple needs and interests. It enables researchers to select a sample based on the purpose of the study and knowledge of a population. They choose subjects because of certain characteristics.
The primary objective of this type of non-probability sample is to produce a sample that is representative of a particular population. This is done by using the researcher’s expert knowledge of the population and selecting a sample of elements in a non-random manner.
Another major advantage of this type of sampling is the wide range of sampling techniques that researchers can use across different qualitative research designs. Typically, qualitative research designs involve multiple phases and require different types of sampling techniques at every phase. Purposive sampling becomes useful in this situation, because it offers a wide selection of non-probability sampling techniques. For example, a researcher can use critical case sampling to determine if a phenomenon is worth investigating further. Then, he can use expert sampling to examine specific issues.
Various purposive sampling techniques allow researchers to make generalizations from the sample that is being studied, whether these generalizations are logical, analytic and/or theoretical in nature.