To work against a customer's preconceived or ill-conceived notion is usually not the right path to take if you want to make sales.
It is like Big Pharm
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. Joe feels a little down and he reads a magazine ad or sees a TV commercial that tells him Prozac is the answer. He goes to a doctor (you, in this scenario) and before the doctor can tell him he really just needs to eat better and exercise, Joe demands Prozac.
The fact that the doctor is an expert and actually has a personal face-to-face with Joe means nothing. The TV ad promised everything.
The doctor's expert, healthy advice is disregarded because Joe has his mind made up before he went to the doctor.
The doctor won't prescribe Prozac because he sees it as entirely too expensive and unnecessary. So Joe goes off to a doctor that will give it to him at a premium price and not care about Joe's best interest. The doctor gets to charge Joe a whopping visit fee and the big margin on the drugs.
That is the same scenario most of you will face. You want to be the caring expert, but your reward will be the door hitting your butt on the way out the door.
We bid a 10-gig job that one of customer's wanted because the CEO read an article in Sky magazine on a flight that said anything less is a huge mistake. His mind was made up, there was no point in trying to educate him.
Two or three other companies really pushed CAT5e and wouldn't even bid a 10G solution. Their bids were not even looked at, ours was, and we made a lot of profit at probably 4x-5x the price of the other bids.
Ask any salesperson - give them what they want or someone else will.
Another frequent example are customers who have voice cable in place but insists on an all-IP phone system because it is 'better.' No use asking him/her why she believes that, TOO LATE.