Five Common Cliches (done wrong):

The early adapters will use it.
Actually, they're adopters, not adapters. The mistake in wording represents a fundamental misunderstanding of how most markets work. People don't adapt to what you make, they adopt it. They can't be forced to adapt, so they won't.

Half my advertising works, I just don't know which half.
Actually, it's closer to 1% of your advertising that works, at the most. Your billboard reaches 100,000 people and if you're lucky, it gets you a hundred customers...

Let's do a focus group, they'll decide.
A focus group is supposed to focus you, not them. It's supposed to lay out ideas and issues that mean little to the group and plenty to you. If you're not prepared to focus, better to not go.

That's a wacky idea.
Actually, doing what you're doing now is wacky. Because what you're doing now is certain to become obsolete, possibly sooner rather than later. Just ask my old boss!

We need a bigger marketing department.
Probably, you need everyone in the organization to do the marketing... from scratch. More brochures aren't the answer.