I work for myself now. I sub for other contractors. Many of them hire Hispanics because they work hard and need only basic skills. My neighbor in Oracle, his son is an electrical contractor in Tucson. He says the same thing I do. He can hire Hispanics and they'll work hard but you can't leave them unsupervised or they'll take shortcuts. He also says they're unwilling to attend classes or training to get advanced skills for the most part.
Here in AZ, I find a sure sign that a poorly qualified Hispanic worked on something electrical to be there's electrical tape everywhere. Nicked insulation on a wire? Electrical tape is the answer for them. Wire nut won't cover all the stripped wire ends? Electrical tape. Don't have the proper connecting device or wire nut? Twist the wires together and electrical tape. Their attitude seems to be It works and you can't see it in the finished product...
Rather than use the correct screw or such, they'll put in whatever they have that seems to work. Can't tell you how many plastic boxes I've seen ruined by using something like a drywall screw because they couldn't take the time to get the correct one and do it right... That means, me coming behind them to fix something, I have to cut out the box and replace it taking the better part of an hour to replace say a switch and get the correct screws in place to do it right rather than taking ten minutes to replace just the switch. I see this all the time.
In one apartment I completely rewired, the Hispanics on the drywall crew covered up a half-dozen of my boxes. The contractor was pissed when I came bitching about that to him. He had to tear the entire ceiling out of the kitchen pantry because they dropped it leaving my box like a foot above their new ceiling. Just sloppy work.