you know, we got the same problem here with arabs in Israel. negligence and laziness is the definition for most arab workers here.
*for example- my father's boss, who happens to be christian arab from nazareth, the dude's a "mechanical engineer" so called, "finished" my university (the Technion, and by the way i also study this field of engineering). now, the guy is an imposter, and poorly does his job and my dad actually gets often paid for finding his mistakes.
*another example- arab garage workers- got my car to a garage to fix a leaking air conditioner. the arab "mechanic" takes a look and then asks me in confusion:"but what causes it??" yeah i know what causes it, thats why i gave you the car to look and pay you for something i already know. and no, the leak wasnt fixed.
however, i must say there are many cases i know in which Jews (most the cases i know relate to the morrocan Jews somehow) dont do their job either.