TIPs on hiring an artist:
When you select an artist to create something for you, choose them based upon the quality of their work and their reputation and professionalism. Can they meet your deadline? Are they responsive to your requests.
Next, communicate your expectations but don't tie their hands. You chose them, because you trust them based upon their work and reputation, therefore, give them freedom to create. It will show up in the work and you'll delight in the results.
This drawing is lively and shows a "delight" because the clients allowed for creative freedom. They communicated well beforehand, approved the drawing, requested that a simple little item be worked-in, and the results:
CLIENT REVIEW of this caricature: "IT LOOKS AWESOME! THANKS SO MUCH"