Steriods in essence is not harmful to your body if taken the right amount. I know bigmack was/is an expert in this field but he is banned I presumed. The drawback for me is the acne. I was prone to it when I was a teenager and I sure don't want to have them again.
Here is a forum dedicated to steroids if you want more info
For some people it is very hard to grow muscle. The body peaks at a certain level and steroids help you gain more muscle mass. Granted, there are side effects to them but the gains are almost guaranteed if you follow a strict diet and workout. I have personally never tried steroids but am very curious about them.
If you work out correctly you don't need steroids except u want to become super big. Super big is unattractive and to be in shape and become big you don't need them, i you know how to work out and work out hard.