What happened to me once was that I actually got the staff position on a server, since everyone agreed to it.
When they asked for my Skype, I complied and gave it to them and when I first spoke, all of these adult staff members immediately asked how old I was. Then they said I was too young, and banned me from the server for "trolling."
To be honest, I highly doubt what I was doing in any way was trolling, and if I was that ill-intended, I could have easily messed up the server when I first became op.