I forged my customer's signature
What kind of a reason do you have to forge someone's signature?
He didn't give me the raise that I deserve and I hate him.
Forging signatures is very illegal. You could go to jail for that.
Nah, I doubt anyone is going to find out.
What if he does find out though? You didn't get the raise you thought you deserved from him, but if you are arrested for forgery, you will have a very hard time getting a job at all in the future.