It may be tempting to assume that users will navigate across dialogs, creating a dialog stack, and at some point will navigate back in the direction they came from, unstacking the dialogs one by one in a neat and orderly way. For example, the user will start at root dialog, invoke the new order dialog from there, and then invoke the product search dialog. Then the user will select a product and confirm, exiting the product search dialog, complete the order, exiting the new order dialog, and arrive back at the root dialog.

If AI struggles with fourth-grade science question answering, should AI be expected to hold an adult-level, open-ended chit-chat about politics, entertainment, and weather? It is thus encouraging to see that Microsoft’s Satya Nadella did not give up on Tay after its debacle, and Amazon’s Jeff Bezos is sponsoring an Alexa social chatbot competition. I love this below quote from Jeff:
Today, more than ever, instant availability and approachability matter. Which is why your presence should be dictated by your customer’s preference or the type of message your business wants to convey. Keep in mind that these can overlap or change depending on your demographic you wish to acquire or cater to. There are very few set-in-stone rules when it comes to new customers.
When one dialog invokes another, the Bot Builder adds the new dialog to the top of the dialog stack. The dialog that is on top of the stack is in control of the conversation. Every new message sent by the user will be subject to processing by that dialog until it either closes or redirects to another dialog. When a dialog closes, it's removed from the stack, and the previous dialog in the stack assumes control of the conversation.
Interface designers have come to appreciate that humans' readiness to interpret computer output as genuinely conversational—even when it is actually based on rather simple pattern-matching—can be exploited for useful purposes. Most people prefer to engage with programs that are human-like, and this gives chatbot-style techniques a potentially useful role in interactive systems that need to elicit information from users, as long as that information is relatively straightforward and falls into predictable categories. Thus, for example, online help systems can usefully employ chatbot techniques to identify the area of help that users require, potentially providing a "friendlier" interface than a more formal search or menu system. This sort of usage holds the prospect of moving chatbot technology from Weizenbaum's "shelf ... reserved for curios" to that marked "genuinely useful computational methods".