In this case , no new reinforcers were contacted and learning to open the backyard door ( that has a special latch ) was effectively a waste of time .
The child 's parents do n't usually approve being alone in the backyard .
In this case , no new reinforcers were contacted and learning to open the backyard door ( that has a special latch ) was effectively a waste of time because the child 's parents do n't usually approve being alone in the backyard .