Product-market fit is the stage at which a startup has built a product that satisfies a strong market demand, evidenced by accelerating, sustainable customer adoption. The phrase was coined by Marc Andreessen in his 2007 blog post "The only thing that matters," where he argued that product-market fit is the single most important state in a startup's life.
Andreessen's original definition is direct: "Product-market fit means being in a good market with a product that can satisfy that market." It is the product-side analog to [Founder-Market Fit] on the team side. When you have it, customers buy the product as fast as you can build it. Usage and revenue grow without aggressive paid acquisition. Customers refer other custome...