It really depends Without staging environment, your chance of finding critical bugs rely on offline testing. Not all bugs can be found in unit tests, you need

It really depends Without staging environment, your chance of finding critical bugs rely on offline testing. Not all bugs can be found in unit tests, you need load tests to detect certain bugs that doesn't break your program from correctness perspective, but on latency/memory leakage front. And such tests might take longer time to run. Staging slows things down, but it is intended, it creates a buffer to observe behavior. Depending on the nature of your service, it can be quite critical.