> It's always surprised me that Yelp, like Flickr, and other early services, became stagnant when the mobile transition happened ... Why didn't Yelp early on see that they could become OpenTable, or GroupOn?

I don't understand where this line of thinking comes from. Yelp has nothing in common with Flickr in regards to their business performance or somehow missing mobile.

Their business also hasn't grown stagnant in the mobile era, it has grown dramatically: 10x sales increase since 2011 (six fiscal years). If that's a failure to transition, it's one every business on earth would like to have.

2011: $83m in sales

2013: $232m in sales

2017: $846m in sales