I am your greatest asset, or heaviest burden,
I will push you up to success, or down to disappointment
I am at your command,
Half the things you do might just as well be because of me,
I am easily managed, just be firm with me.
Those who are great, I made great.
Those who are failures, I have made failures
I am not a machine, though I work with the precision of a machine and the intelligence of a person.
You can run me for ruin, or run me for profit.
Show me what you want done. Educate me. Train me. Lead me. Reward me. And then I will do it automatically but be easy with me.
What am I?