You may recall from a prior lesson, that the manufacturing revolution in the 1980s, witnessed a dramatic decrease in lead time. Which predicts quality, customer satisfaction and employee happiness. According to Dominica Del Grande, one of the leading experts on using Con Bond with devops. Controlling queue size is an extremely powerful management tool, as it is one of the few leading indicators of lead time. With most tasks We don't know how long it will take until it is actually completed. Here Q size is analogous to the amount of work in progress. In other words, if we want to decrease lead time, then we must control what's being worked on at any point in time. In this video, we elaborate on why we should limit work in progress. How Con Bond helps with this task, and what to do when you're stuck waiting on someone else. [MUSIC] Manufacturing plants have a tightly controlled production schedule that dictates the order in which jobs are processed. This schedule is certainly based on customer orders and promised delivery dates, but also considers inventory, and the availability of resources required for the job. Why do manufacturing plants operate this way? The reason is that disruptions are expensive. For example, it might require several hours for a machinist to reconfigure a milling machine for each job. This time is effectively lost because no products are being produced while the machine is reconfigured. In addition, when a job is stopped before its completion, the incomplete work may have to be scrapped or at least stored temporarily. In contrast, I T work rarely follows a predetermined schedule. We're accustomed to juggling multiple jobs with different priorities, and receiving requests in the form of work tickets, emails, instant messages, phone calls and face to face interactions. Prioritizing appropriately can be a major challenge. Research also indicates that individuals performance degrades significantly when multitasking. Even for simple tasks like sorting geometric shapes, which means that we're rarely able to operate at our best. Let me try to make this cost more concrete. Some years ago I attended a lecture by Randy Pausch about time management. I learned that interruptions typically last between 6 and 9 minutes. If that isn't bad enough, we needed an additional 4-5 minutes to refocus after the interruption. Before that, were mentally trying to please work with my computer science analogy page, the memory that we swapped out to handle the interruption. If you do the math to interruptions in an hour results in almost half an hour being lost. Even a short interruption, such as looking at a text message, still breaks our concentration and degrades our performance for several minutes. [MUSIC] Now, you might be thinking that interruptions are a fact of life, and you cannot eliminate all of them. You're right., yes we do need to be aware that our work practices sometimes sabotage our own productivity, just like disrupting jobs in a manufacturing plant. So how do we limit multitasking in the number of interruptions that we experience? Con Bond, which we saw earlier, offers one approach to managing work by limiting the amount of work in progress. For example, we might only allow our team to have six cards in the in progress column at any point in time. When we reach this limit, one of those tasks must be completed before starting a new task. So what happens when you find yourself waiting on something, should you start a new task to remain productive? Know, the best action is to help the individual you're waiting on to finish their work, so that you can resume and complete your original task. Why is this strategy preferable to the alternative? Well let's say that you started a new task instead, and it takes you the next day or so to complete it before you resume your original task. No harm, right after all, every task must be completed at some point. Unfortunately, what we often fail to realize is that someone else is waiting on our original task, and we've delayed their ability to complete their work. If we want to reduce lead time, then we must limit our work in progress [MUSIC]