Kwixesha lokwenziwa kwezinto ngobuchule, ukuzisebenzela kwemizi-mveliso kuye kwaba ngumkhwa ongenakuguqulwa, kwaye iirobhothi zokuwelda, njengesixhobo esiphambili kwicandelo lokuwelda kwemizi-mveliso, ziye zathatha indawo yokuwelda yendabuko eyenziwe ngesandla kwiimizi-mveliso ezahlukeneyo.
Ngenxa yokuchaneka kwazo okuphezulu, ukusebenza kakuhle, uzinzo kunye nokuthembeka, iirobhothi zokuwelda azisombululi nje kuphela iingxaki zokusebenza kakuhle, ukungaguquguquki kakuhle kunye nobunzima obukhulu bokuwelda ngesandla, kodwa zikwaphucula umgangatho wemveliso ngempumelelo, zinciphisa iindleko zemveliso kwaye zincede amashishini ukuba afezekise ukuphuculwa kwemizi-mveliso.
Eli nqaku liza kwazisa ngokupheleleyo irobhothi yokuwelda yemizi-mveliso kwiinkalo eziphambili zokuthengisa, iiparameter zobugcisa, iimeko zokusetyenziswa, iingenelo zemveliso kunye nenkonzo yasemva kokuthengisa, ukuze kuncedwe abathengi baqonde ngokupheleleyo ixabiso kunye namandla emveliso.