Market Place Start Up - Should I Measure?

Market pac sat up. O, at which stage do we have to start measuring the product market it? Because i finger mentioned ta soves ar envid by es, but only pasers mey be accurate to measure. Nd, experimentation, decide what is the best decision. Probably does n't mater right now, but it will mater some point. Do we have time of custions, right? A couple of questions, yes, sir ther. Anno startsou. The question was, if i'm in market place start up, at what stage should by measuring? Should i be measuring prag market?