I think he just means overall. Indeed, the quality of the cards suffer when you DIY them, but I guess I'm willing to make a teeny weeny bit of sacrifice on that for my own back designs. Actually it doesn't take a lot of work, because most of the time designs are relatively fine to do, and the printing's not my business - I just collect the final product, give the guy the moolah and we say goodbye to each other for the day. See, I use cards for a lot of purposes, not just normal magic, and I need a combination of branding, quality and cost per deck. I could definitely get a brick of Vipers or something but if I go around using them at one deck a day I'll lose money faster than I earn it.
However, seeing as you mentioned you were designing cards with the intention of getting people to purchase them, then I'll fully agree with you.
1) Top Quality
2) Nice design, and nice printing of design
3) Good Finish, Stock and Long Lasting
4) A good card box to go with it
(4) is exceptionally important. I had a friend who went to a proper printer to print his cards, and everything was good. (He was printing quite a large run). The design was fine, the finish was passable but they came wrapped in shrink-wrap, and for all purposes that makes the deck like... single use unless you have a lot of spare boxes on hand.
Well at any rate, if anyone knows where I can print good quality decks with small runs (something along the order of maybe say, 5 decks at best?) Please do let me know as well. Most of the time the problem with printing good quality cards (I think Kal-El might have encountered the same problem) is not that there's no lack of printing companies, but they print like 10k decks each run, which for the poor magician like me will be enough to cover my room walls and flooring twice over.