Decorator on selector causes the wrong node to fire

http://puu.sh/wc1Yq/b80df8b549.png

This is the most basic I can make it and still show the behaviour. Is Stunned Decorator checks if the stun timer of the AI has gone down to zero. It still executes even if the timer is not zero. It works if I do this:

http://puu.sh/wc2uk/4b798cdd4d.png

Why does the decorator not work when attached to the whole selector? I dont want him to chase the player if he is stunned. Instead this selector should fail so I can play the stunned animation instead.

Thank you for your help.

This problem can be solved by using a service (at higher node, selector for example) that reads the timer and switches nodes using the value of the blackboard variable. This variable is a trigger for blackboard based decorator.

190458-untitled.png

I was not wondering how to make it work, but more why it didnt work when I put it one step above. It should skip the entire tree, but it doesnt.

What are the return values of the decorator (debugging)?