Go ahead, let me back in to your system after you fire me. I dare you.
Let’s see...Fifty years of undocumented program modifications, line after line of dead or stunt code, misleading comments, etc. What could go wrong if an H1-B makes a few minor changes here and there? After all, they were taught good programming practices and strictly follow all the rules in the books, But real programmers know its like a sewer down there and things can get really dirty in hurry if you don’t know what you’re doing, namely the traps, pitfalls, and what to avoid. It’s an art and experience comes with a price. Not to say there aren’t any good H1-B programmers, but many should be working at Mickey D’s for their $10/hr, not on critical software. Put H1-Bs and complex related systems together and you have a potential disaster lurking in your IT systems long after the H1-Bs are gone.