The theory is that Netflix maximizes their profit by decreasing the monthly rentals of heavy users with a series of various delays. Here are the most common tactics that Netflix could use to slow down your flow of DVDs. Note that this section is theoretical and can be proven
conclusively only with internal Netflix documents.
Late Afternoon Shipping
Netflix sometimes ships DVDs in the late afternoon. This makes it harder on the post office to get the DVDs to you the next day. This often adds a day to your turnaround time.
Netflix will not always check-in your DVDs on the day that they arrive. Netflix will sometimes increase your turnaround by simply holding your DVD for a day or two.
Netflix should send out your replacement DVD the same day they receive your returned DVD; however, they often push your ship date back a day. This allows them to automatically increase your turnaround time by a day on each DVD.
Alternate Distribution Center
Netflix will send your DVDs from alternate distribution centers that are outside of your local area. Depending on distance, this tactic can easily add an additional two or three days to your turnaround time. (See Comments for details.)
Netflix will hold your replacement DVD and ship it so late in the week that it is almost impossible for the DVD to arrive before Monday. This throttling measure not only adds days to your turnaround time, it can leave you irritated all weekend.
Netflix will sometimes throttle you by "losing" a DVD for an extended period of time. This missing DVD tactic will effectively reduce your three-out plan to a two-out plan. This virtual plan downgrade can go on indefinitely. When this happens, the burden is placed on you to discover the problem and report the issue to Netflix. Each time this happens to you, you will probably end up having to report the DVD as lost to restore your full flow of DVDs. Even though Netflix will almost always blame USPS for the missing DVD, there have been many reports of Netflix suddenly "finding" DVDs when customers start asking questions.