Constant playtesting to improve a game is the major path to success in game design. You have to do it the right way, though. Many tips from a retired game design teacher & creator of Britannia.
If you're doing it right, one of the hardest parts of game design is writing clear rules. How to do it varies with your audience. Improve rules as you playtest. Includes Do's and Dont's handout.
Of Course You Can Design a Game, but Can You Design a Good One?
Summary:
What does "good game" mean? A lot of different things to different people. But there are principles to follow before you use playtesting to determine your target market's reaction.