When working as a graphic designer, it is common to come across a situation where a client wants something that goes against your better design judgement. The client will often insist on a certain style or design direction, even if you, the designer, thinks it does not serve his or her overall goals. Clients will also often turn to a friend or family member for advice, and again come back to you with an opinion that you do not agree with.
Often the best way to deal with this situation is to explain to the client your reasons behind the design decisions. Rather than saying "because I said so" (or some variation), come up with valid points to back up the creative side of the project. Tell the client why their customers will relate to the design better, why the design will generate more business, or why you made decisions for technical or budget related reasons.
Hopefully, after some reasoning, the client will see why your decisions are not just based on your taste, but on the client's best interest. However, clients will often insist on certain creative decisions, and so it is also beneficial to think of a compromise ahead of time.

