A hypothetical example derived from that earlier
comment of mine:
You are a speaker maker, and curious about what could be achieved by a unique combination of motion feedback and neural network correction of a bass driver. You work on it for a while and then listen to it. It's astounding; it sounds more like real bass than you've ever heard. The motion feedback on its own got close, but the neural network refinement compensates for some of the unavoidable cone flexing at high accelerations and the result is a step change in bass reproduction.
At this stage, your experiment is genuinely objective, scientific: you haven't 'voiced' the speaker by listening to it; you have merely closed the loop with feedback on the measurements and you can document everything as being 'objective'.
But you decide to do some real 'science'. You assemble a panel of listeners and, because you are doing science, you don't tell them what they are listening for. You play to them a selection of commercial speakers (volume matched to within 0.1 dB, etc. - all that good stuff) and also your new speaker. You ask them to give their 'preferences'. Sound is the only variable in play.
You put the results through the statistical analysis. To your dismay, you find that your new speaker is in the lower reaches of the rankings. Science has proven that your idea was schiit. You abandon the idea and scrap the project.
Your paper is published though - you have to get something out of it. Other speaker makers and scientists read it and take it as a warning; passive bass reflex boxes actually sound superior. Science has proved it.
What happened? The answer is that the listeners came with preconceived ideas. They knew what a 'good' audio system sounded like, because they own expensive ones themselves or have heard them at shows. Your speaker sounded nothing like those 'good' systems, and in fact shocked them; they had never heard those recordings sound like that before. Your speaker must just be a freakily bad speaker.
By committing your work to 'science' you fooled yourself. You took an objectively correct system and put it through a subjective non-scientific experiment, but included the 'usual' sleight of hand of putting the participants' subjectivity in a black box.
Had you, instead, declared in a big advert that you had produced a radically better bass driver, and asked listeners to evaluate it on that basis i.e. told them what to expect (shock horror - non-science!!!), you might have had a smash hit on your hands and been able to sell the idea under licence to other speaker manufacturers.
But looking on the bright side, you got your name on a published paper.