When somebody in your town decides it's time to try CrossFit, they pull out their phone and search for a gym near them. They read what your members wrote about you, they read what people wrote about the box down the street and the Planet Fitness on the corner, and then they pick one place to walk into.
That's why we think Google reviews are the most important thing a box can do to grow. A review costs you nothing but the ask, and the one a member leaves in March is still on your page in November when the next person is deciding. The more of them you have, the more likely you're the gym they find when they search (no promises about where Google puts anybody), and the people reading them pay the most attention to the newest ones.
Think about what one member is worth to you in a year.
The person who reads something recent about your gym, walks in instead of going to the chain, and stays for years is worth that every year they're there.