ITERATION! Gangmaz understands the need for this more than any other designer I've worked with on 99designs. Most of the time, we (the customer) don't know what we want and we need to see multiple iterations to brainstorm what we want.
Gangmaz produced 15-20 designs (5 completely different themes) within the first DAY. This helped my team get a really good idea what we wanted early on. He is responsive.