There is actually a really logical reason for this, it's a bit difficult to explain, but since your PSD is initially an IMAGE, actually coding it out to look exactly that way requires extensive knowledge in CSS, HTML, and positioning. It took me years to get it down perfect, that's why I charge a lot, and usually turn down 95% of the work thrown at me.
IF the website designer who created the PSD just created it without taking into consideration whether whatever they created is even possible without lots of additional code, the quote that you were given was most likely too low for them to care about ALL the details. It sucks, I tried outsourcing some of my designs a couple of times, and they come back as if these idiots didn't even look at the PSD. BUT that was because there was a lack of web development and implementation knowledge and know how on their side.
I'm a firm believer that website designers also need to be able to code out what they are designing. If they can't it's like an architect making a building in a "C" shape and giving it to the builder to make it work. It is not structurally sound, and it would be nearly impossible for the builder to build it correctly. But these dumbass website designers coming out of college who have never edited html think their designs look cool, and it's up to the coder to implement them. It works both ways, idiots. You can't give a spaceship design to someone that builds race cars.
If a website designer can't code, I pass on them. That usually reduces the field by 98%, because there are very rare few that can code correctly, fully know CSS, HTML, javascript, and functionality to make a website design work AND have a great design as well.
Somewhere along the line, I don't know where, but website designers stopped coding, and left that up to coders, which baffles me. In my definition of a website designer, they should be able to code their designs, otherwise they are just a fucking illustrator. Maybe programming javascript is not necessary, but basic understanding of CSS. html, and delivering a barebone skeleton html to a client should always be a requirement. I've got enough skills to chop up a PSD and make it look like the actual mockup, I've rarely seen that in all my years, and when I do find someone that can do that, I latch onto them.
There also is a lack of understanding from a consumer standpoint of deliverables of a website and what a quote consist of. Most people don't have a great understanding of what it takes to get a real website up, so the only gauge they have is pricing. So when they can't tell what coding is quality and what's shit, they'll just haggle over pricing, so now it's an industry where the cheapest quote gets the job. But that also means the best designers/coders end up doing their own thing and not even entering the market, like me, since all the end consumers know is "low price", "my nephew can code a website and he is 16". I make sure all my code is W3C validated. All html elements are valid. The CSS is valid. The website is cross browser compatible, and the code is clean and minimal. Plus it's lightweight for speed, and all the images are compressed and speed optimized. Is your 16 year old nephew going to do all that, or even understand why I do what I do? Do they even know what the gzip compression codes does in the .htaccess file?
For me at least, it's gotten to the point where I do all my design, coding, and implementation for my own projects, and turn down any other projects, just too much of a hassle to deal with people that don't know what they are doing.
If you claim to be a website designer and can't code, you're a waste of space. If you claim to be a coder but can't design, you've got some uses, like updating websites, but you're not a professional in my opinion. It's not a difficult job, a website designer should create a design then make it live. What the fuck is so difficult that you need 3 people to do the job of 1 person?