Because you enabled it: "Spawn vehicle in the direction you are looking at" = true.
If you do not move position, it will always spawn the vehicle where you are looking

But the problem is that the recalling does not work, or is that not intended? Do you always need to use kill? recall sounds like it should "recall", aka remove from the map so you can then spawn again when you use the command.

e.g. this sequence of commands would make more sense to me
/horse -> horse spawns
/horse -> horse disappears
/horse -> horse spawns again

or this
/spawn horse -> spawns horse
/recall horse -> horse disappears

Otherwise I don't see the point of having /spawn, /recall and /kill, 2 of them would be enough

/recall means to move the horse back to your vicinity.  I think it works all the time. 
/kill triggers the cooldown, while /recall does not.

I think most people like the way it works. 
/horse -> buy a horse
/horse -> spawn a horse
/horse -> recall a horse

If you think there's another good way to work, you can tell me, and if most players think that's a good way to work, I'll add it

Ok, I see, that makes sense. Thanks for the clarification!