the 1st thing to go is details and the most important part of engineering is on paper for others to build where it all starts with a good Spec.
We need to show the way of a good design starts with clear expectations on what you verify when it does everything you want and avoids everything you dont want.
This is called a spec. even if it fits on a paper napkin.
An answer can be no better than the question in details.
Although often overlooked in designs, the Environment is a critical part of the spec.
Climatic; Temp and humidity, sometimes altitude, Salt spray Operating, non-operating, shipping
Mechanical: Shock & Vibe , Operating, Non-Operating and shipping.
Electrical: Power/ Voltage range, EMI Ingress ; Susceptibility Conducted, Radiated (modulated RF, line impulse, ESD) EMI Egress ( AC Conducted, Radiated),
Reliability: Power Cycling, HALT, HASS , Margin Stress Testing.. Mil-Std-Hdbk-217 etc.
Design Stds: for Cost DFC, for Test DFT, for manufacturability, DFM, for excellence, DFX
One only needs to look at any production power supply and expect all of this to be documented.
Sadly rookie designers aren't taught this, unless they have good mentors or Corporate or Military Standards.
I was lucky to have all of the above right from the start. in '75.