I started Crossfitting after buying a livingsocial deal for the Elements (intro) program. I started as close to a beginner as you can be. Not in good shape. From the first class, I knew that this is not like a regular gym. You don't do your own thing, they have a different structured workout daily. If you need help with your form, the coaches are righ there to help you. I have appreciated how well they modify the workouts to be at the right level for each person. I also love the feeling of community at Crossfit702. If you miss a few days, you will hear about it from someone when you go back.
I describe it to my friends as a PE class for adults, but way more fun, because the hard work comes with noticeable results. Who wouldn't love that?