The Lean Startup
Although the MVP will be far from perfect, it should not compromise on the core of the product. It can have bugs or missing features, but the most important aspect should still be high quality.
For example, if your goal is great customer service, you can handle many parts of the MVP manually. This ensures great service while giving you time to learn exactly what customers want before investing time into building features. You will also learn the biggest pain points of your business model, letting you automate these first.
Your MVP can take many shapes. But it is always measured against the growth criteria most important to your business model.
If your business is to grow through the viral effect, every features you deliver should make it spread faster. Any feature that doesn’t achieve this goal is a failure. With every failure you learn which paths not to travel.