It has always been a basic principal for me that perfection is something to be strived for but rarely, if ever, achieved. But just try and tell that your customers!
So many times I have had a customer tell me, "I want it perfect." And I usually respond by telling them that perfection can get quite expensive, whereas getting close to perfection will be much more affordable.
Some accept this. Most respond with something to the effect of: "I'm paying good money here and I want it to be perfect." At that point I will typically share with them the estimated up charge to go from "close to perfect" to "perfect." That is usually enough to convince all but the most stubborn customers that close to perfect is really quite acceptable.
But there are still those who insist on demanding perfection. These customers require special handling. I tell these customers about my special "cost is no object, nothing but perfection will do" package. I call it the "Time and Materials Job."