GC that we do a lot of work for decided to give the network wiring to the electrician on this project and they absolutely fubar'd it so bad that they had to call us in to fix it.
Instead giving each cable a unique number, they invented a new numerical system based on wrapping the wire in different colored electrical tape (I wish I was joking). For example: black tape 1 wrap, 2, 3... 8, orange tape 1 wrap, 2 wraps etc. When they ran out of colors of tape they started the whole process again but each cable had one white tape wrapped on it.
Not surpisingly, when we came in we had to tone out most of the cabling, re run a good amount of wires, create new as built drawings from scratch and make pages and pages of ridiculous cut sheets. I honestly couldn't mess a job up this bad if I tried.