Evernote

Evernote grew from about 10 to 100 million users, but a generous free plan, a $45 a year tier that avid users valued at hundreds of dollars, and pricing left unrevised for years limited revenue. With no growth loops, paid acquisition tapped out. Bending Spoons bought it for about $200 million on $90 million revenue, cut staff from about 350 to 20, and ships three times faster. Lesson: build loops and revisit pricing.