Boundary condition checks that run only within each contractor's model file let piping clashes appear only after the civil package has already poured its foundations. The PMO system registers each internal clearance as complete and releases the next progress payment.
Interface registers track scheduled file exchanges rather than verified property-set compatibility. Electrical and mechanical teams upload their IFC models on time while the structural grid remains offset by 40 millimetres in the shared coordinate system.
Commissioning then discovers the misalignment during first equipment placement. Every party points to their approved internal model and the change order queue balloons because no single contract owns the shared datum.
PMO tools that score milestone completion by file upload date reward this fragmentation. They never surface whether the receiving package could actually consume the delivered geometry or tag data.
Capital program directors therefore inherit a growing list of latent interface defects that only surface under live load. Cash has already left the project and the original contractors have demobilised.
The fix requires interface milestones to include automated clash and schema validation across all active packages before any payment is released. Without that rule the multi-contractor model stays a collection of independent drawings rather than one operable asset.
Boards that continue to accept per-package sign-offs will keep funding the same post-handover rectification spend they claim to be reducing.