That's why Hitman 2 Silent Assassin introduced the Silent Assasin rank which consists of... being a silent assassin, and not kill anyone but the target. Because, you know, 47 is a silent assassin... Like the title says.That is not the point, the guy is tasked to kill a target. How you do it is up to the player. Rank is not story. It's like getting cops after you in GTA with 5 stars for being an obvious killer. You score by killing your target based on the choices you made. The rank is just to give people a shot at picking up points on leaderboards. Nothing more.
Also: https://www.youtube.com/watch?v=AkrUJJgQAaY