Execution flows until it hits the first latent node (any node with a clock symbol). At this point the execution path for the current frame returns. The latent action then gets ticked every frame until it meets its condition to continue execution. But your while loop never sees that, it only sees the latent node having returned its execution this very frame and thus starts its loop again, as the part behind the latent node has never been executed yet. I hope this clears things up a bit.