I was CTO of an analytics startup in the early days of MongoDB hype. We built on MySQL. One of our competitors was MixPanel. We were having scaling issues with

I was CTO of an analytics startup in the early days of MongoDB hype. We built on MySQL. One of our competitors was MixPanel. We were having scaling issues with one particular customer, so I looked into the various solutions. They all looked pretty cool, but I didn't like that the developer communities were small compared to MySQL and PostgreSQL. So I ended up sticking with MySQL and building a simple sharding mechanism that allowed us to move big customers to their own server if necessary. It worked great. While I was working on that, MixPanel published a long, highly detailed blog post about why they had moved to MongoDB. That led me to have second thoughts. "If these guys are doing it, maybe we should too?" But I was pretty far down the sharding development path and couldn't justify making such a wholesale change based on one blog post. Fast forward about nine months, and MixPanel published a new blog post about why they had moved off MongoDB. Vindication! Ever since then I've had conservative disposition when it comes to deploying new technologies.