Convenience samples refer to a method of sampling that is not based on probability. The samples are usually taken from people who are easily accessible. This is why it is not desirable because the data maybe biased and therefore the result may not be a representation of the entire population.

The higher the size of a sample, the higher the expenses incurred in the process, the data obtained is of better quality because it gives more information about a population or group.

The major difference between the two sampling methods is that cluster sampling relies on the entire group as a unit of sampling while in stratified sampling the unit of sampling is just a subset of the whole population. The similarity is that the methods are random.