S14KA24DE won't start possibly starter?

Dude it’s a starter…
Cranking+Grinding+No start-Battery=Starter… Correct?

Tried the lock thing and no go. Was the starter. Changed it out and in doing so saw the the starter ground was rotted off. Got one used for $40 and its noisy but it works. Dont wanna throw any $ at my KA anyway.