If a client asks you to design a direct-mail postcard and their copy, offer and/or mailing list sucks, it's time to step in. The messengers always get killed, and if your client deploys a crappy campaign, you'll be blamed for its failure. They wouldn't be erroneous in their ways – you, the designer, would be the responsible party in their minds. Speak up!
Sure, it takes some gumption to look a client in the eye and tell them they are a bad copywriter, or that nobody is going to care about their offer, or that they don't even know who their prime customers are and should really reconsider their mailing list. But the worst that could happen is that you could be thrown off the job and get a reputation for being arrogant. That's better than getting a reputation for failed marketing campaigns. Arrogant people know what they're doing. That's why people hate them so much, but it's also why people hire them so much. Now, I'm not saying you should behave like a pompous ass and gleefully tear into your clients' copy as they look on in horror. But there's no reason you can't gently explain that your professional experience tells you that the campaign could use some tweaking. And if all else fails, try to convince your clients to run tests of different postcards against small cross-sections of their list to determine which is more effective. They should really be doing this anyway. Telling your clients that they need to make a change can be painful, but earning an undeserved reputation for being unable to convey a message is a business-killer. Image use Creative Commons via Flickr.