Why build an MVP?
The main goal of an MVP is to develop a working product that provides immediate value, quickly, while minimizing costs. Starting with an MVP will allow you to learn more about your end-user and the market you wish to enter as you test your assumptions. An MVP will also set the stage for future iterations of development and clarify the sequential steps to take in the project - whether that's changing directions entirely, or continuing down your set development path. In some instances, an MVP can also be used to showcase business potential and win stakeholder buy-in. Whether you're looking for support from internal or external investors, an MVP definitely strengthens your position, as it proves the merit of your product and secure funding for future development.
Premature optimization is the root of all evil, as D. Knuth said. Also, fail soon, fail often fail cheap, but fail forward 
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Walkthrough by pictures:
