Allow me to explain it this way.
CoolBlue dileverd us a MathTeacher. The manual says we have 2 actions and 1 condition.
Action 1 = Ask the dude to solve some mathproblem. ('Ask')
Action 2 = Tell us the solution. ('Tell')
Condition = On the moment that he knows the solution. ('On known')
Manual also states that he takes some time to find the solution.
So what we do ?
We start with the action 'Ask'
Then we make a top-level condition
'On known' paired with the action 'Tell'.
Now we do other stuff, like watching tv, and change some pampers, and wait till the dude is ready.
All this time we make sure that we and no one else feeds the dude a new mathproblem, got to wait till he is ready. Else he will go crazy. And we lose the warranty.
When the dude is ready, the 'On known' triggers, and the dude tells us the solution.
What did you do ?
You start with 'Ask' followed by 'Tell', under a trigger !
But the dude is not ready yet, so he cant tell yet.
So when he's ready he's holding his breath, eager to tell. But he cant, the actiont to 'Tell' is caged under that trigger.
So the next time you use 'Ask' followed by 'Tell' that fast, the pure dude is stuck on what to do.