The Selector executes its children sequentially from left to right.
If one of its children returns either "success" or "running", it will halt execution of its children and it will return the result of the child it stopped on.
If all of its children return "failure", the Selector will also return "failure".
Sequencer
The Sequencer executes its children sequentially from left to right.
The Sequencer will not halt execution of its children unless one of them returns "failure" or "running", in which case it will also return "failure" or "running".
If all children return "success" the Sequencer will return "success"
Multitasker
The Multitasker runs all of its children concurrently, each in a separate thread.
The Multitasker will return "success" only if all of it's children return "success".
If any of its children return "running" but none return "failure", the Multitasker will return "running".
If any of its children return "failure", the Multitasker will return "failure".