According to the author of 2 Samuel, the watchman sees someone running and thinks it looks like Ahimaaz. The king believes Ahimaaz is a good person who brings happy news.
2 Samuel 18:27: And the watchman said, Me thinketh the running of the foremost is like the running of Ahimaaz the son of Zadok. And the king said, He [is] a good man, and cometh with good tidings. [Me...: Heb. I see the running]
This verse implies that a way can seem right to a man but end in death, contradicting the positive implication of good tidings associated with a good man in 2 Samuel 18:27.
Proverbs 14:12: There is a way which seemeth right unto a man, but the end thereof [are] the ways of death.