My favorite examplei is naked SQL vs an ORM. The ORM will never be able to write queries that perform as well as if you write them all by hand. But, you'll be

My favorite examplei is naked SQL vs an ORM. The ORM will never be able to write queries that perform as well as if you write them all by hand. But, you'll be able to crank out functionality much faster. Eventually, if you're lucky, you'll have enough traffic to warrant going back and rewriting some of the ORM calls using a SQL query optimized by hand. Lastly, 99% of the time, the query you end up optimizing will not be the one you expected to when you started writing the app. That's because between when you started and now, the direction has changed significantly and you finally know what it is that you're really building.