[mbseid]

I also think a lot has to do with language and deployment. Etsy uses PHP for their entire codebase. PHP can be easily hot swapped without any overhead. It's all scaffolded and thrown out every pageview. This provides a much simpler deploy process and has much less impact.

Java on the other hand takes time to warm up. It just isn't practical to redeploy the whole app when you are just updated one aspect.