Why does your lawn mower starter get hot?

There are three reasons for it to get hot:

1. Its is bolted to the engine and the engine is hot making the starter hot
2. It has been used for longer than intended and not allowed to cool properly. !5 seconds max crank time followed by two minute cool down is a good rule of thumb
3. There is something wrong: Low voltage or poor battery, A bad or poor connection between power source and starter, The engine has a problem causing the starter to work harder than intended or the last possibility is that the starter is faulty and drawing to much power making it heat up.