Are there standard metrics to gauge process complexity?

One aspect of user experience in a software application or website is the complexity of the processes involved in completing a user task/goal. It probably comes as no surprise that if the steps required to complete the task is long and complex, then the user will have a difficult time getting a good user experience from trying to achieve his/her goals. Off the top of my head I can only think of things like the number of screens and clicks as quantifiable measures. I would like to know if there are any standard metrics used to measure the relative degree of quality of content that takes into account of various elements that comprise of process complexity, and how this relates to the overall user experience.