Why is the customer service so bad

over the phone even the supervisors like we are the ones paying for your job just to be rude to us doesn't make me wanna continue any kind of business with them just to have supervisor and reps just cut u off and not let u finish till the point that I started swearing and everything just to not be able to call them anymore they need better training or better people i just don't get talking down to ur customers and expecting them to be nice when they r rude