I can't stand it when signs say this! Ninety-nine times out of a hundred, it's definitely causing me an inconvenience! (If it weren't, I probably wouldn't be reading the sign.) Why can't they just be men about it and say, "We're sorry for the inconvenience"??
If I weren't a pacifist, I'd find the guy who wrote the sign (latest example: the printing station by my favorite bank of computers is down), kick him in the crotch, and apologize for any discomfort that may have caused.