Why is it locked!!??

Question

I was like walking up there and then there was the door and i tried to open it but they were like "no it's locked" and i was like "what the heckk!" and they were like it's sticking out so it's locked and it was like this metal thing and i was like "wtf." cause there wasn't like a lock there was just this thing on the door like 2 inches tall and long and i just like stuck out and they said it was locked and it was but im really confused!! please help me!!

Answer 1

I don't understand the whole idea.
I got that its lock, so if its locked- that means
no one should pass through.

Answer 2

something doesnt want anyone on the other side.