You would think that. Then, oops, we're running dash, not bash. Or that sinking feeling you get when you think "that command line switch worked last week" on so

You would think that. Then, oops, we're running dash, not bash. Or that sinking feeling you get when you think "that command line switch worked last week" on some "mature and stable" Linux utility only to realize that you're no longer running bash with real utilities, but ash with toybox or busybox builtins because some dickhead wanted to save 5 MiB on his docker image.