system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does our brain sometimes go into "autopilot" and when/why do we snap out of it?

Sometimes people go into autopilot and can make some mistakes (big or small).  Why do we do that and sometimes continue until we fucked up?
gpt
Because you are probably thinking of something else, thereby using your conscious thought and forcing your subconscious to take over. But your subconscious only learns from watching your actions throughout life, so it might not be good at some things but better at others.

Take driving, for example. When you first began learning to drive you needed to focus all your attention on that action, but as your subconscious has been observing through the years it has been learning, which is why a lot of people can space out driving somewhere and suddenly realize they've reached their destination. Their subconscious took over as autopilot while they used their conscious mind to ponder the past, future, or whatever shit they wanted. 

But your subconscious does not know how to perform some actions, and might fuck up. Hell, you might not even realize it. That's why some people act just like their parent and everyone sees it but them. Because it's their subconscious mind acting that way. They're on autopilot. The real trick in life is to be aware of the present moment and truly be yourself, so when you do ponder some bullshit your subconscious will hopefully have learned enough to actually be 'you' while on autopilot and not just go through whatever motions it has been programmed to perform of which you're probably not even aware.