- f ounded ▁us ability ▁consult ing ▁company ▁N iel sen ▁Norman ▁Group ▁with ▁fellow ▁us ability ▁expert ▁Donald ▁Norman . ▁ ▁Cont ribution s ▁N iel sen ▁founded ▁the ▁" dis count ▁us ability ▁engineering " ▁movement ▁for ▁fast ▁and ▁cheap ▁improvements ▁of ▁user ▁interfaces ▁and ▁has ▁invent ed ▁several ▁us ability ▁methods , ▁including ▁he ur istic ▁evaluation . ▁He ▁holds ▁ 7 9 ▁United ▁States ▁pat ents , ▁mainly ▁on ▁ways ▁of ▁making ▁the ▁Web ▁easier ▁to ▁use . ▁▁ ▁N iel sen ▁gave ▁his ▁name ▁to ▁N iel sen ' s ▁law , ▁in ▁which ▁he ▁stated ▁that ▁network ▁connection ▁spe eds ▁for ▁high - end ▁home ▁users ▁would ▁increase ▁ 5 0 % ▁per ▁year , ▁or ▁double ▁every ▁ 2 1 ▁months . ▁As ▁a ▁cor ollary , ▁he ▁noted ▁that , ▁since ▁this ▁growth ▁rate ▁is ▁slower ▁than ▁that ▁predicted ▁by ▁Moore ' s ▁Law ▁of ▁processor ▁power , ▁user ▁experience ▁would ▁remain ▁band width - bound . ▁ ▁N iel sen ▁has ▁also ▁defined ▁the ▁five ▁quality ▁components ▁of ▁his ▁" Us ability ▁Go als ", ▁which ▁are : ▁▁ ▁Lear n ability ▁ ▁E ffic iency ▁ ▁Mem or ability ▁ ▁Error s ▁( as ▁in ▁low ▁error ▁rate ) ▁ ▁Sat isf action ▁ ▁N iel sen ▁has ▁been ▁critic ized ▁by ▁some ▁graph ic ▁design ers ▁for ▁failing ▁to ▁balance ▁the ▁importance ▁of ▁other ▁user ▁experience ▁consider ations ▁such ▁as ▁typ ography , ▁read ability , ▁visual ▁c ues ▁for ▁hierarchy ▁and