how old are the polishes? will you purchase them new? they should all be the same age if you want a proper test. are you going to test them in different ranges of activities? (washing dishes, raking the lawn, school day etc.)

are you going to test them as is? or are you going to test them with base coats/top coats?

how about different ages of people? perhaps they last longer on teenage hands than adult hands?

are you going to test each category and then see which one last longest out of each and THEN test these against eachother?

the question you are asking is very vague and general so you’re going to have to do a lot of testing!