New graphic designers often worry about their tangible skills. Am I a master of the pen tool? Am I adept enough at HTML & CSS to offer my services? Can I design a print piece to print specifications? Rightfully so, these are areas that all designers should be concerned about (amongst others).
If you're working on a creative project for your business - new sales literature, a website, campaign materials, etc. - how do you know when your concept and design is "good enough?"