This happens to me constantly, but I only design a small part of my work week. I imagine this happens to full time designers enough to drive them mad.
When you send a Photoshop document to another designer, pay some attention to how the layers and groups are named. It’s really hard managing the file of someone else where everything in it is named Layer 2, Layer 2 copy, Layer 2 copy 8, etc., etc. The first thing I generally do is start toggling the visibility of each to figure out which is which and naming things accordingly. But ironically, this has even burned me in the past. The sender actually had the nerve to complain that I wasn’t able to send the file back with changes because it no longer matched his “layer structure”.
And you know, I guess I also disrupted the communication as now we can’t refer to Layers in the file: “Look at Layer 13 copy 12. No, no, the other Layer 13 copy 12 in group 3 copy 6.”
I’m just saying, garbage in, garbage out. Show some professional courtesy before you send that PSD.