If you don't want to think about things like redundancy then use higher-abstraction services. Lambda for example takes care of multi-AZ redundancy so you don't

If you don't want to think about things like redundancy then use higher-abstraction services. Lambda for example takes care of multi-AZ redundancy so you don't have to think about it. The lower level building blocks like EC2 don't. They expose the fault boundaries so that you can build HA applications on top of them, but it's still your responsibility to do so.