Customer is king
In any industry, your customer is the most important. Without your customer you don't have a substantial business. In my years of designing, pleasing my customer has been my focus. When I client has given me a brief, to crack that brief has been my objective. What the customer says' goes'. Your art your direction on what works and what doesn't work visually should guide your customer so not only supplying them with what they want but also with quality.
Occasionally, my customers have asked for really boring and plain designs, that to be honest I wouldn't want to but my name on, but with a bit of convincing I have helped them deliver a better design!