I am fairly new to this myself but here are my thoughts. It depends on the quality of chicken you want. If you don't care about breed standards, showing and those types of things and just want chickens to breed for eggs and such then hatchery chickens are ok.
If you are wanting to show chickens or preserve a breed, I am going to venture to say many on here would tell you to search out good breeders of the breeds you want to raise. I am not saying you can't get good chickens from a hatchery but chances are more likely that you will get better looking chickens from a breeder. Just my 2 cents.
That said all of my chickens so far are from hatchery stock. I just use mine for eggs.
I like to buy hatchery stock to see if I like the breed of bird, if it works well in the heat of Texas and what kind of eggs it lays. Gets too broody or whatever. If I like it THEN I buy from a good breeder, if not I try some other breeds.
Depends on what your goals are. I would do research about the breed you are looking for first. Many times hatchery stock is not a good representation of the breed in shape, color, size, or temperment. If you are serious about breeding for show or to at least be able to have birds that fall into the standard of perfection, you should definately look for a breeder. But do your research there also. Not all breeders are the same, and not all breed for the same thing wether its egg production, egg color, bird size, or bird showing.
Best advice is research research and yes more research. If you don't do your research, you cannot blame anyone but yourself if you didn't get what you wanted, where ever you got it.
In my choosen breed. You can't get them from hatcheries.