One can greatly increase performance via skillful management of a contractor.
I have had great contractors, mismanaged others, and had to get rid of a few. From various industries:
Video editors, accountants, graphic designers, lawyers, real estate/rental agents, photographers, etc..
Independent of industry, the same problems occur:
The work is not up to your client's standards.
The contractor is not punctual to meetings, deliveries, and email responses.
They aren't returning you phone calls.
Poor Management Example
6 months ago, I hired a talented web designer in Egypt to create a WP theme for $500. Paid upfront.
He sent me a link for the rough draft. It didn't work. I contacted him twice oven the next 48 hours and no response. I paniced at that point I called ODesk and said I couldn't get in touch with a contractor.
3 hours later, I get an angry email: “I was on vacation and I just got back. I am sorry the link didn't work, but you shouldn't have called Odesk like that. I refunded your money in full.
Then on Skype chat, in all caps: I AM NOT A THIEF
That was the end of our relationship. It was an unlucky coincidence that the link didn't work AND that he went on vacation.
He had great reviews. It never crossed my mind, even after 48 hours, that he took the money and ran. But I called his “boss” and that was out of bounds by his standards.
In the big picture, I wish I would have had more patience and seen his design. He would have done a better job than the designer who replaced him.
Good Management Traits
When I have success with a contractor, I usually exhibit the following behavior:
I don't negotiate. I pay them above their hourly rate. This shows the designer that I trust, them, that they deserve what their worth.
I clearly explain the task. I tell them what I want and am quick to clarify confusions. I get them what they need.
If you delay response to emails and phone calls, they have a justifiable excuse not to work. “I can't work until X requirement is sent/paid/designed”
Finally, I am able to communicate that something is high-priority or essential without bothering them.
By trial and error, things have gotten better. Contractors should have a pleasant experience working with you, and it is your job to create it.