There’s no reason to shut it all down if 1% of your request to a web server gets a 500. This is more like finding a bug in production and having all the devs s

There’s no reason to shut it all down if 1% of your request to a web server gets a 500. This is more like finding a bug in production and having all the devs stop working (including merging more changes) until it's fixed. Customers can still use the end product, you just stop making new things until you've solved the problem. There's some undeniable logic to doing that if you value bug free over fast.