The answers given reflect my opinion on the subject as well...
Ever hear that commercial for the clothing store "Syms". Their motto fits here very well.
"An Educated Consumer is our Best Customer"
That pretty much sums it up.
I had written a long explanation...but truth be told. A detailed, well laid out, well dimensioned print is our road map to producing a quality part to customers specifications. I need to know which features to be careful with, I need to know what feature doesn't really need to be held to tight tolerance. I need details.
A Road Map that has just an Outline of your State with Two Points and an arrow with no streets, highways, doesn't show rives, lakes, obstacles is not much of a map...is it? If you had to call mapmaker to ask for more info...you know your in a losing battle. Easier to just use a different map maker.
A bad drawing tells me a customer does not know exactly what they want, they need and that is a problem I Do Not Wish To Take On. I have plenty of my own problems, I do not need to take on that customers too.
So what happens when that sort of drawing comes across my desk...At first I go, hmm, maybe a nice job...further look...hmm, Lots of missing info, wrong info...I'll put over here till I have open time. AND There it SITS...I have a pile of folders like that myself.