On January 15, CSI fans will officially say goodbye to the character of Gil Grisson.

After nine years on the show, William Peterson is leaving the top-rated series. He explained why to Entertainment Weekly:

''It's CSI — they pay me a lot of money, and I don't have to work very hard anymore... And I just realized, God, as an artist, I'm going to atrophy. You do anything for nine years, it becomes somewhat rote. I didn't want to be on the show because they were paying me money and I liked the money," Peterson said. "I didn't want to be on the show because it saved me from having to go look for other jobs. Just didn't want it."

William Peterson and the CSI cast on the set for the actor's last episode.

A week before his final episode airs, Peterson isn't overly sentimental:

"I won't miss Grissom. It was a complete life for me that's reached its end, and it's reached it in the right way, I think. So I won't miss Grissom. And I hope that the audience won't miss him, either."

Matt Richenthal is the Editor in Chief of TV Fanatic. Follow him on Twitter and on Google+.