Who said it showcased Sinatra's talent? I agree, though, that Sinatra had many other songs which would better showcase his talent. I can think of eleven on my favorite list:
1. I've Got You Under My Skin
2. Strangers in the Night
3. That's Life
4. Fly Me to the Moon
5. Come Fly with Me
6. My Way
7. The Way You Look Tonight
8. Theme from New York New York
10.Night and Day
11.Summer Wind