Why it's hard to be a trial lawyer

I had lunch with a friend the other day. He's one of the smartest and hardest working lawyers I know. The kind of guy who reads every decision and knows every nook and cranny of the law relevant to his field. He was telling me about a couple of cases he had. In one, he won the unwinnable case. In the other, he lost the unloseable case.We make decisions as trial lawyers. Should we have a jury