The systems administration life would be an awful lot easier if we never had to deal with other people (and I'd imagine those other people would say much the same about us).
So, let's talk about developers. Our developer friends are doing their job, developing. It's in the nature of computing that no software is perfect, and bugs will creep in to even the most beautiful of code; it can even pass its previous tests, run perfectly in development and preprod environments, only to bring down production.
You can think you've got a solution working perfectly, running like a dream, purring like a cat, and then one new "feature" from a developer can seemingly bring an entire solution crashing to the floor. It can be tempting to look for someone to blame in these scenarios. However, I would instead urge calm and composure, because...