Technical skill
Program state unambiguity principle
Requires to write programs in such a way that in any given moment it was clear how program reached that state (spefically from stack trace or even log files)
Skillsets
Materials
If you know useful resource, that helps to get this skill, please, spare a minute and add the link
Question
Questions are very useful when trying to understand if you know the subject
Do you know that ...?
Any useful or interesting facts about the skill. Any peace of information would be useful