Assume that a store manufactures N guitars. Every guitar has a probability P, of being defective. If I buy a guitar, and it turns out to be defective, does it change the probability of another guitar being defective?
One way to see it is that every guitar is manufactured independently and hence the probability shouldn't change.
Another way to see it would be once everything is manufactured, there is a finite fixed number of guitars that are defective (let's call it X, which is approximately PN). So finding one defective guitar implies the probability of finding another defective guitar becomes less : ((X-1)/(N-1)) instead of (X/N).
I am tempted to assume that each guitar is in a quantum state (mutually non-entangled, obviously) such that before we check a guitar, it is in a superposition of defective and non-defective. Which supports my argument but I am not able to convince my friend (or myself) why that should be the case in a classical system.