I'm curious what all goes in to that stat. Is it the ensuing possession after every single time out? Or is it(somehow) only calculating situations that call for a coach drawing up a play to score?
Your team goes on an 8-0 run. I call timeout to stop that run and quiet the momentum. We inbounds the ball under the opponents basket and bring the ball up like normal, and very likely run our set offense. We score or fail to score out of our set offense.
It's a 1 point game with 8 seconds left. We call timeout and draw up a last second shot to try for the win. We score or we fail on the attempt.
These two situations are very different, and presumably both fall under the ATO stat