As an aircraft maintenance engineer I must admit I´m rather shocked by some of the advice above.
Leave it slack? Put it on the wrong way? It doesn't MATTER? Have you people lost your minds?
David got some really sound advice up there. That spinner is going to kill someone if it comes off at 50mph. Yes, that .41 lockwire will hold it on - if done correctly. No, it won't if you put it on backwards, too loose or worse - not at all.
And since we only have one photo up here to judge (sorry David), its got too many twists
pr inch on the end, it wasn't twisted far enough towards the spinner so the final twists are slacker than the rest and opening up. Its a bit difficult to see the angle on the wire in this shot - but common rule is 60* maximum angle from anchor to whatever is safetied.
The wire must never be reused and even though we want it tight - not so tight that vibrations will overstress and brake the wire.
*Rant mode OFF*