SPOILERS FOR SEASON 3
When Jaime loses his right hand, he has a gold prosthetic made. Then he has to re-learn how to fight using a sword in his left hand.
Why didn't Jaime get a prosthetic made that includes a sword/weapon of some kind? Like a prosthetic hand that is holding a sword, or a hook, or something more practical? Then he could have continued to use his right hand, or at least have an easier time re-learning how to fight. Something that he can switch to when he knows that he's going to fight.
Answers from books and/or shows are acceptable. (I personally have not read the books)
EDIT: Understandable that this is seen as opinion-based. I am not sure if there was some discussion of what to give Jaime for a "new hand" in the books or some spoken dialogue that I could have missed. Otherwise, I believe there could be a non primarily opinion-based answer (Mwr247's answer below) which makes sense, but I also believe Mwr answered part of the question (why not a sword) when there is still something I think could be answered.