Typically configuration changes tend to have much more impacts compared to implementation codes at the same line counts hence its consequences are less predicta

Typically configuration changes tend to have much more impacts compared to implementation codes at the same line counts hence its consequences are less predictable. Also, it usually coordinates multiple systems at once, so it is much harder to test especially when it comes to a capacity problem caused by complex interactions among multiple systems. Canary or gradual roll-out cannot reliably catch this class of problems, since it's not really visible in a small scale.