execute command cannnot store Motion nbt correctly

command like "/execute store result entity @e[type=cow,limit=1] Pos[1] double 10 run scoreboard players get zsm_3fps test" could work when zsm_3fps has a score of the scoreboard test, but "/execute store result entity @e[type=cow,limit=1] Motion[1] double 10 run scoreboard players get zsm_3fps test" could not work. 

1.summon a cow

2. creat a scoreboard called "test"

3./scoreboard players set @p test 10

4.try this "/execute store result entity @e[type=cow,limit=1] Pos[1] double 10 run scoreboard players get @p test" and this "/execute store result entity @e[type=cow,limit=1] Motion[1] double 10 run scoreboard players get @p test", see if they works.