Thereasonisprettysimple: indensetraffic, ifeveryonemergesearly, theymaketheopenlaneunnecessarilyclogged, while a longsectionofperfectlygoodroadsitsunused.
Instead, trafficexpertsrecommendsomethingcalledthezippermerge: carsdriveinbothlanesupuntilthemergepoint, andthentaketurnsgoingthroughit, closingliketheteethof a zipper.
Onereal-worldexampleoftheproblems a zippermergecouldsolvecanbeseeninFortCollins, Colorado, attheintersectionofSouthboundLemayAvenueandEastHorsetoothRoad,
TherearetwoleftturnlanesonLemay, buthere's thething: mostpeopleplantoonlybeonHorsetoothfor a hotsecond, beforetheymake a quickrightturnbackontoLemayrighthere.