It's completely depending on the guy doing the install, a lot of whom are outside contractors. Most FIOS installers probably aren't this terrible. We had the same issues with installs when I worked for Speakeasy. Some techs are awesome and some are fucking terrible. Though as a general rule, Verizon East (Northeastern chunk of the country) are fucking horrible bastards both on the phones and in the field.
You'd have things like a dude stopping 5 minutes short of fixing a job because it was 5:00PM on a Friday and then he wouldn't come back until the next Monday or something. Unions are so great.