Challenges should have a timer

challenges should have a timer that saves and is posted to friends. Not that you have to beat the clock, rather a way of tracking how quickly you shut a challenge down. It would increase competition amongst friends, yourself and provides a metric to show improvement. It also gives incentive to repeat challenges.

furthermore, it will prevent players (myself included) for just turning around on the bearings challenges and slowly reaching all objectives to shut the challenge down. 

a timer which saves your best score and friends best scores would incentivize players to complete the objectives as they were intended in a line and often at high speed