Kingdon tries to answer why some subjects become prominent on the policy agenda and others do not, and why some alternatives for choice are seriously considered while others are neglected.

• 金顿的理论建基于垃圾桶模式，尝试解答为什麽某些问题可以进入政策议程，而其他的却不可以；为什麽某些备选方案得到决策者的青睐，而其他的却受冷落。