The Failure to Fill The Gaps is linked to environmental and ethnic (less affluent) bias, with the more affluent areas being able to outright stop a freeway, diverting the traffic burden disproportionately upon less affluent areas.
A textbook example is the failure to complete the missing link of I-95 in western New Jersey from the Trenton area to the vicinity of the southwestern corner of I-287, which makes it less convenient for traffic to use I-287 to go around New York City rather than staying on I-95 via the Trans Manhattan and Cross Bronx Expressways.`
Known as the Somerset Freeway, it was the original planned route for Interstate 95 in New Jersey. Besides offering a direct route between New York City and Philadelphia, it would have also offered a bypass of New York City for those traveling to Upstate New York and New England. The plan was killed in 1982 when it faced fierce opposition from communities along the route fearing sprawl and development. Today the sprawl and development is well in the region nearly thirty years later.