Pros
if you build relationships internal you have a great chance in advancing in your career. The career paths are unlimited. you can start out on the phones making 12.00 hr and end up as a manager in data analytics making 102k annually
Cons
Its convenient but they will lowball you when negotiating pay if your an internal employee considering they already have insight on exactly what your getting paid now so they will consider you receiving a good pay jump from your last position instead of what the market if for the current position your are being promoted to. For example if your new position rand is 60k-90k the will start you off at 60k, knowing that you where making 42k. They will not negotiate, its a take it or leave it.