На тему "высокого bus factor". Его обычно и стараются повышать, разве нет?
В Википедии как общепринятое приводят определение: The "bus factor" is the minimum number of team members that have to suddenly disappear from a project before the project stalls due to lack of knowledgeable or competent personnel. ... A high bus factor is considered a good thing as it means that many individuals know enough...
Противоположное определение отмечается как редкое: There is a rare alternative definition for the bus factor, namely: the number of people who are indispensable for the project. If using this definition, then a high bus factor is considered a bad thing (since the loss of any person included destroys the project), and zero is considered the ideal bus factor.
https://en.m.wikipedia.org/wiki/Bus_factor