There are, however, some potential drawbacks to using stratified sampling. First, identifying strata and implementing such an approach can increase the cost and complexity of sample selection, as well as leading to increased complexity of population estimates. Second, when examining multiple criteria, stratifying variables may be related to some, but not to others, further complicating the design, and potentially reducing the utility of the strata. Finally, in some cases (such as designs with a large number of strata, or those with a specified minimum sample size per group), stratified sampling can potentially require a larger sample than would other methods (although in most cases, the required sample size would be no larger than would be required for simple random sampling).
there are however some potential drawbacks to using stratified sampling first identifying strata and implementing such an approach can increase the cost and complexity of sample selection as well as leading to increased complexity of population estimates second when examining multiple criteria stratifying variables may be related to some but not to others further complicating the design and potentially reducing the utility of the strata finally in some cases (such as designs with a large number of strata or those with a specified minimum sample size per group) stratified sampling can potentially require a larger sample than would other methods (although in most cases the required sample size would be no larger than would be required for simple random sampling)