Eric Karjaluoto of smashLAB makes a really good argument that it does suck for clients and what design firm owners should do improve the experience.
In order to run a prosperous firm/agency, you need to make a concerted effort to treat it just like any other service-based company. While it likely makes you uncomfortable to hear this, the success of creative companies isn’t really about the creativity of your offering. I know world-famous designers who are broke, and complete hacks who live quite a nice lifestyle. Quality, while important, is subjective and can be hard to quantify; the relationships you have with your customers are what will most affect your bottom-line and the long-term health of your company.