Can someone help me explain this looping logic ?

Thanks for helping bro <3
Because i choosed "Do not spawn " in SpawnActor node. so i wanna make sure if it’s not spawn because overlap with other actors (8), it’ll comeback looping at 4 till new location spawn valid.
This’s how i thought :
Set is valid vector = true
While ( is valid vector = true ) loop body will spawn actor with random location in array vectors.
Checking actor spawn or not by Branch node,
if actor spawned exit loop body and going to completed, add actor into array spawned actors.
if actor didn’t spawn so it’s not valid actor and looping again to spawn actor with new location random in array vectors.
Can i asking why i ticked is valid actor spawned be true and connect it with Set node, but it still be false ?