I think I have been watching a bit too many investment related shows lately with one common thing I have noticed is that when people are unsuccessful in getting funding for their ideas or products they end up being aggressive with the investor such as saying how they will regret for not investing with them. The reaction is usually either they hope they do prove them wrong or that they simply chuckle at the notion.
I was just thinking how it must be very unproductive in so many ways to say that as it is essentially burning a bridge. As well, if you have a good idea and are humble about it then I would think it would increase your odds of getting more support for your idea. Like some say, many times in a business or product idea people buy into it because of the person themselves. We all probably seen those moments where a person gets ripped to shreds by a harsh critic only to then see that person get more support and attention from others. Less is more I guess you can say.