So what is this hidden killer you ask?
It's poorly managed designer workspaces - the areas in which designers perform their day-to-day jobs.
Even in complex design projects these workspaces are often managed manually, or with limited automation not fully understanding a true IP-centric design methodology. As a result it's too easy for designer workspace to break resulting in significant lost time to resolve the issue, worse yet they can become out of sync with the rest of the design team resulting in unnecessary rework and missed bugs, or worse still it can result in incorrect versions of portions of the design making it into production potentially killing the design.
The solution is to use a correct by construction approach to workspaces that ensures a predictable IP-centric design methodology that always uses the correct version of all IP in the design (as defined by a central configuration).
In Methodic's latest whitepaper (Correct By Construction Workspaces) such a correct by construction approach is described as well the Methodic's solution to the problem using ProjectIC.