I'm using AWS Lambdas for a project. Every lambda listens on an SQS Queue. This isn't latency sensitive in the sense of user interaction, but I certainly care about latency to a degree - primarily throughput though.

The reason I've chosen this is because I do not want to manage an OS. Patch management is something I am not interested in tackling - it's a hard problem and AWS has it down anyways.

There are other reasons as well (I find ephemeral systems very appealing), but this is the most significant.