I believe it was the fact that he went on his

computer without permission, and this had been a problem earlier in their working relationship. He had been banned from using the computer, and after watching him on the nanny cam he just wasn't doing much work, and spent much of his time texting. The other Chris was handed the work orders that were supposed to be split among them. When the boss says you can't use the computer you just can't.
He also went into the closet where Jeff's personal papers, and tax returns were. This led to Jeff feeling violated.
He also was supposed to take care of the dogs, and the 2 larger dogs were a little rough and hurt the one smaller dog caused an injury and a trip to the vet. The maid witnessed much of this, but didn't want to be involved.
I can't believe I watch this guilty pleasure but I do,,, don't tell anyone!! I also know I would never be able to work for Jeff.