color matching

[57chevyman]

got my truck back from the body shop. a contractor accidentally put a huge scratch on the driver side fender. the whole front flip hood had to be repainted. they painted it twice because the color didnt match the first time. is it standard practice to match a custom color by eye and make no documentation on how to reproduce the color??

theres a local body shop supplier who all the body shops around here deal with... been in business for decades. last summer i had a friend paint my truck with single stage enamel. i bought the paint.. a gallon was around $100 bucks. i brought them my glove box door and they matched it "by eye". when i picked up the paint, i asked for the "code" or some documentation for the formula they used.. they said " our guy matches hundreds of colors a day. we dont document the colors he makes". so i said, ok, what if i need more of this paint? he said, "bring the glove box door in again and he will match it again."