You were Optimus Primes child, so you were basically royalty. One day, when you were in the palace (That was in the middle of the Autobot and Decepticon town), you walked up to Optimus and asked if you could explore the city. But Optimus has told you before, you weren't allowed to leave the palace- AT ALL!

"You wanna risk your life over what? A stroll in the town? You should be smarter than that." Optimus paused "You have everything you need here, what more could you possibly want?”