It's easier clean up and you can set it and forget it.
With my WSM I can't get as many cooks in as I'd like because of the hassle. I know cleanup will be 30 minutes at least and that if I do a substantial cook I'll need to check the temp every hour during the day, every 3-4 hours at night. But, I get better results on my WSM than I do with the same recipes on a Traeger. Also, since it's a hobby, I enjoy the WSM more.