Twelve payments settle the price in full, so at month 12 the piece is simply yours — there is no balloon payment waiting at the end and no approval step.
The choice is open before then, and it is open to everyone. End the lease at any point and you can swap the piece for another one and start a new term, keep it by paying whatever is left of the twelve payments, or send it back at no cost with everything you have already paid credited back to you.
Twelve months is the minimum term only in the sense that it is the length of the schedule. Nothing locks you in for it.