Well, let's talk about this value or demand hypothesis, and how we go through and how we ask and answer these questions. Well, the good news is that, if you have a well-delineated, well-researched problem and persona hypothesis, then these are really easy to frame up, and really clear and they'll help drive a lot of clarity for the team. So for example, in this job to be done, this might look like this job exists, there's this kernel alternative, and if we do something like automate parts lookup and ordering online, then what will happen? What we hope will happen, then the tech's will use it and it will improve outcomes. Now, you look at that and you maybe like, that's obvious, it's dumb to spend time doing this, and that's reasonable, that'll be a lot of people's first reaction. A lot of good design is about asking the dumb questions and getting these things on the board, because usually they're not as obvious as everyone thinks, and they're not as vocal as they probably should be. Then the idea here is that, once we declare this hypothesis which is the first step, then we think about how we would test it, and if you're familiar with the body of WorkAround, Lean Startup, and the use of MVPs, this is a great way to practically test your value or demand hypothesis in a way where you can get quick answers that will help you make sure that you're building something that your user or your customer actually wants, and we're going to work on pairing your hypothesis with patterns that make sense for the particular question that you have. If you're not familiar with Lean Startup and MVPs, don't worry, you will be, by the end of the course. One critical thing to start thinking about is that, an MVP is not a 1.0. Often the two are used interchangeably, but really nothing could be wronger about Lean Startup, the idea is that the MVP is some kind of product proxy that we create so that we don't generate the waste of actually building out a full product, if we're thinking of delivering a value proposition that a customer doesn't actually want, and that's just really the whole point of Lean Startup. Not the guarantee that we'll always be successful, but the promise that we will minimize waste by testing these things before we go and we invest in the process of building and maintaining software. So how do you know if you need this? Well, if you don't have an explicit value proposition that your work is linked to, it's probably a good idea to at least get that on the board. As we'll see, it's probably pretty practical to go out and test it.