So often we try things, not just in photography but in all aspects of life where we feel a pressure to get things right the first time we try them. Score that goal the first time, pass the exam the first time you sit it, ace your driving test on your first go (It took me five attempts!).
In actual fact we learn very little from getting everything right all of the time, and it can even be detrimental to our learning. Over time we get used to being in the know and knowledgeable in our various fields of expertise - and lets be honest, it feels quite good when we are. The reason this can work against us, especially in the learning phase of something is that we can (if we're not careful) build up a barrier and find it very uncomfortable to be told that we can do better or that actually we've gotten something wrong all together. Receiving praise is always nice, however, there's only so much you can learn from "Great job, keep it up." Making mistakes burns a permanent reminder in our brains that we don't want to make that mistake again. There's only one time you'll forget to switch your camera from manual focus back to auto focus during a shoot. It's not a fun feeling. These moments are what really shape our knowledge and experience in photography and in anything else we try.
We have to be able to put our ego and pride to one side to be able to fully soak up new knowledge and experiences. It can be very tough to let that barrier down and be open to making mistakes, not knowing the answer and potentially not getting the outcome you want.
Take for example winning and losing as an athlete. Anyone can win, it feels great when we do. What really tests athletes is the ability to overcome adversity an analyze where things went wrong. This allows them to come back stronger and stand a better chance the next time they compete. The same thing applies in photography.
I've learnt more in photography by making big mistakes than I ever have getting it right first time. I'd even go as far to say that it feels even more rewarding to go through that learning experience knowing how far you've come. Only by getting things wrong can people point you in the right direction. Take a moment and think about how much you knew about your camera or composition before you started learning. Now you're adjusting ISO without thinking about it. You're correcting shutter speed and aperture settings when you need to. You're making all these technical decisions whilst carefully composing and taking an image.
Throughout your time learning photography I'd say get it wrong and get it wrong again. By making mistakes when you're learning, you'll hopefully never have to make them when you're out on a shoot.