Practice makes perfect. We have heard that over and over again but the ones that actually listen and take this to heart are the ones that succeed. Earning anything doesn't come easy and you must work for it. This rings true in life and the gym. We do advanced movements in CrossFit. In order to use these movements correctly and fluidly one must practice over and over again in order to establish proper movement patterns. For the majority of people, these movements do not come naturally so we must practice to make it happen.
WODs are the perfect opportunity for practice. Not everyday is a competition. Don't do these workouts as prescribed if your form is flawed, you are just reinforcing bad habits or allowing injury to happen. Higher weights will come more quickly if you develop good habits from the start.
If your squat sucks, you should not have a barbell on your back. If your overhead squat sucks you should not be full snatching anything. If you are unable to do a proper push up why do you think doing ring push ups are better? Take the necessary steps to get better and you will!
Slow down and learn the movements and do them well before you jump to higher weights or a higher skill. Jumping ahead before you are ready inhibits great growth.