He did not care what it took to get there.
Banquo is very loyal to duncan, he is very honest, and reliable. When the witches predicted he wouldn’t be king he didn’t get mad or upset. He was satisfied that his future generations would become king. After king duncan was killed he was loyal to macbeth to an extend. His character kind of distanced himself from macbeth kind of like he knew that macbeth killed duncan.
Duncan