Sometimes the product have not been polished, or it's a concept, so you need to sell the product before even showing it. Once the customer has made his/her mind

Sometimes the product have not been polished, or it's a concept, so you need to sell the product before even showing it. Once the customer has made his/her mind they are unlikely to change it. And then you work with the customer to improve the product to meet their expectations. Meanwhile if you would have shown the product/prototype without any selling they would have made up their mind and never come back or given any feedback. I know you are a busy person, and so am I - I just want to see the damn output, I don't have time to run it and see for myself even if it just takes 10 minutes. But if I'm not willing to do that, then it's very unlikely I'll invest in it anyway, even if it's very good.