Why doesn't this work?

It's supposed to create a armor stand at player's position, then move it randomly, then tp it 10 block up and then the player teleports to it. But the armor stand just stays at player position and then tp's ten blocks up. When I delete the kill line and run 'execute as @e[tag=random_teleport,limit=1] store result entity @s Pos[2] double 1 run scoreboard players get @s pos_z' in game, only then does the armor stand move to the correct location. Does anyone know what the problem is? Also I'm sorry if my english is bad, I should work on it.