www.coursera.org/lecture/digital-health-design-implementation/human-centered-design-in-practice-ajFbP
This is a link to an excellent 6' video (under 5' at 1.25x speed) that was part of the Coursera course I was taking on Digital Health. It gives a great overview of the principles of Design thinking and Prototyping. Some of the key takeaways include:
- Design research goes beyond market surveys by chatting with people one-on-one to hear their stories, understand the associated emotions and gain tacit knowledge. This is achieved through asking open-ended questions and then sitting back and listening.
- Prototyping is not a skill but a mindset. Prototypes should follow an Agile-style process: quick, simple and frequent development as well getting feedback as often as possible. To maximize the honest feedback, remove yourself from the process by saying, "This is what the designers/others/team came up with, what do you think?"

As outlined in my 2015 article entitled “No Magic = No Business Opportunity,[1]” I define Magic as:
"that extraordinary, remarkable, sensational, fantastic and brilliant phenomenon. Every good business or business opportunity is built on its own special bit of magic. Magic is the differentiator that customers value and competitors can’t match."
 
I go on to identify a number of possible means to uncover your Magic: Examining the job-to-be-done, Identifying customer fear or greed, or Providing superior value. I then outline ways to defend your Magic: Obtaining Intellectual property rights, Securing a unique or limited resource, Establishing a strong customer connection, or Building structural advantages. Uncovering and defending your Magic is critical to establishing a viable business.
 
But, how do you ensure your business opportunity has sufficient Magic? This third criteria is something that experienced entrepreneurs, mentors and investors often have a good sense of, having seen what it takes to bring an opportunity to a successful conclusion. However, it is often difficult for a budding entrepreneur to assess, especially when examining their own opportunity.
 
There are four ways activities that all entrepreneurs should undertake to satisfy this third criteria:

1. Prepare as detailed a business plan or Business Model Canvas[2] as you can. This will ensure you’ve explored the various aspects and assumptions underlying your opportunity.
2. Seek out mentors and leverage their experience to provide you with ongoing advice and feedback as you develop your opportunity.
3. Become your harshest critic at scheduled intervals. Every few weeks, stop the planning and execution for a moment and assume a devil’s advocate role.[3] Alternately assume the role of the customers, competitors and regulators/government. What are the weaknesses of this opportunity? Why might customers not buy? How could the competition threaten your success[4]? How could new regulations or changes in the industry derail your goals[5]? One creative way to facilitate this is to brainstorm (i.e. suspending evaluation) a list of as many issues that could affect the business opportunity as possible (aim for 100!). Once completed, review and prioritize the top 3-5 issues and work on means to resolve them and incorporate the solutions into your business planning exercises.
4. Enter pitch contests or pitch your opportunity to investors. These events and especially the associated audience questions and comments are sure to challenge the Magic of the opportunity[6]. These activities are, of course, not recommended until your plans are well refined.  

An additional means to get a better understanding of Magic is through observing and analysing the pitches and plans of other entrepreneurs. Attending pitch competitions, getting involved with an business incubator or accelerator,[7] and speaking with other entrepreneurs will increase your exposure.
 
As I wrote in 2015, “In order for a business to remain viable or a new business opportunity to succeed, it must serve a customer segment well and defend against competitors who wish to do likewise. This requires the business to be operating under some magical influences: a unique value proposition. When looking to innovate you need to ask yourself two questions: “What magic is my business built on?” and “Is there enough magic to succeed?” because your potential stakeholders including investors or senior management (for internal projects) will be considering them as well.”

[1] http://hexagoninnovating.weebly.com/1/post/2015/04/no-magic-no-business-opportunity.html
[2] https://en.wikipedia.org/wiki/Business_Model_Canvas
[3] "One who argues against a cause or position, not as a committed opponent but simply for the sake of argument or to determine the validity of the cause or position." 
https://www.urbandictionary.com/define.php?term=devil%27s%20advocate
[4] https://en.wikipedia.org/wiki/SWOT_analysis
[5] https://en.wikipedia.org/wiki/PEST_analysis
[6] UofT’s Entrepreneurship Hatchery simulates these activities through monthly pitch events in front of a panel of experienced individuals.
[7] https://en.wikipedia.org/wiki/Business_incubator

It is important for the teams of early-stage companies to keep a razor-sharp focus on the customers and market they are hoping to address in the context of the product or service that they are developing. Validating the opportunity with potential customers as quickly as possible ensures that the team’s efforts and limited funds are being applied effectively. If this is not the case, the team can adapt or pivot their idea, or recognize the idea as a fast failure and move on. Validation is achieved by developing, demonstrating and discussing successive prototypes, and the so-called Minimally Viable Product (MVP) to an increasingly larger number of the target customers.

This urgency to validate opportunities at an early stage has a key operational implication: The initial plans should “niche down.” What is meant by this term is that efforts should be initially confined to a single, focused and limited offering, addressing a small niche market within an easily addressable and serviceable territory. In effect, this focus should be on the “minimal” of the minimally viable product (MVP). Like a patent application, the focus should be on demonstrating the novel, inventive step and little else. In doing so, the team can expedite an initial proof of concept (POC) i.e. validate the feasibility and desirability on a small scale and/or small, focused market and then expand the offering from there.[1] Developing and launching a novel product or service is an experiment as one cannot determine the customer response in advance.
 
Despite such a strong initial focus on the core offering, innovation and differentiator, success will still require that the longer-term market potential be huge. Often the term used is that the product or service must be scalable.[2]  Scalability means that with additional resources (cash, staffing, partnerships, and manufacturing capability) and proper execution (marketing, sales, distribution, integration and service) significant growth and revenues can be generated. This combination of a proof of concept (POC) with a plan to scale is what will attract early-stage investors. For them, risk reduction and market potential are far more important than a feature-packed offering. Additional features and benefits can be added as the offering evolves.
 
On the other hand, it is easy for teams to overextend or become distracted by all the possibilities while building out their initial business plans. Efforts to show strong future revenues and profits as well as a significant competitive position help drive this tendency. Common examples of overextension are plans to become: a one-stop shop, the low-cost producer, a global presence or all-things-to-all-people. These things may indeed come to pass, think about the wide offerings of the FAANG companies (Facebook, Amazon, Apple, Netflix and Google) and Microsoft, but even these businesses started much smaller and focused: Harvard student connector, Online book sales, Home built personal computers, DVD rentals by mail, Improved search engine, and Operating system for early personal computers respectively.