Language is a very powerful tool and the way you express yourself will affect whether your proposals are received positively or negatively.
Even when you are conveying unpleasant news, the impact can be softened byt the use of what we call positive language. Everything you say to your customers affects their thoughts and emotions. If your customers are in a cheerful mood they are more likely to agree with your proposals. Therefore your choice of words and phrases can create a positive emotional reaction within your customers.