Tofautisha re - engineering/redesign na kuupgrade, kuanzia L1 - L20 zilikuwa na matatizo maana yake engineering problem.. Kwenye engineering kuna kitu kinaitwa prototype ( first product) ambayo ndio itakuwa pilot ya product zote za namna hiyo utakazozalisha, prototype ikiwa na makosa maana yake product zote utakazozalisha lazima pia ziwe na makosa mpaka hapo user au engineers watakapogundua na kuja na claims ambazo ndio zitazaa product improvement program, sasa hiyo improvement program kama itakuwa ni redesign kutokana na makosa makubwa ya kiufundi kuanzia kwenye structural, engine, transmission, braking system na hydraulic system inabidi ufanye vitu viwili amavyo ni kuscrap the existing product popote ilipo, kustop uzalishaji wa hiyo product na kuzalisha nyingine na kuipa model nyingine na Ile ya zamani ukaiacha kama itaonekana haina madhara kwa jamii na mazingira..