When designing an experiment a benefit of larger sample sizes would be more?

An experiment with large sample size would mean that the results of experiment are more reliable. If sample size is small, then the results of experiment can be biased and can be due to some specific factor present in that small size. However, as sample size becomes large, the variation also increases, and if results of experiment remain consistent despite the variation, then it means that the results are reliable and not because of other factors present in sample members.