The ninjas are all gone due to a basic lack of trust. I suppose trust is hard to come by when you are training assassins.

Presumably this guy’s teacher knew 1001 ways, but held one back from him. Holding back one technique seems like a reasonable plan at first, but not if you follow it out to its logical extent. Each subsequent generation of ninjas had one less technique to use. There is a limit to how far this can go.

And once that limit is reached, you’re done. Where do you go from there? The kid with the throwing stars is obviously the last ninja. You can’t teach now; only threaten.

And that’s why there are no more ninjas today.