Ubushushu obuphantsi kunye nevalve yoxinzelelo oluphezulu, umbhobho woxinzelelo, ubunjineli bolwelo, izixhobo zokomba ioyile, izixhobo zentsimi yeoli, ibhayisekile esongwayo, imoto yabantwana.
1. Umphezulu ogudileyo, umsebenzi ogqwesileyo.
2. Ukuchaneka kwentambo ephezulu, kunokuphucula umgangatho jikelele we-workpiece.
3. Ufakelo lukhawuleza kwaye lulula, kwaye i-nut ehambelanayo isetyenziselwa ukudibanisa kunye nokukhawuleza.