Okay, so this misconception regarding what Hearthstone is needs to be cleared up, as more and more people come into the game because warped expectations ultimately harm the relationship between consumer and developer, so facts need to be set straight.
The reason for printing bad cards, and ultimately more cards, is unabashedly to artificially raise the price of playing the card game. For if all the cards were almost perfectly balanced, then it actually becomes easier for players to create a competitive deck and so they spend less, whereas if there are only a few rare power house cards, then more card packs will be purchased.
David Sirlin responded with a pretty compelling counter argument on his blog post "Balancing Multiplayer Games Part 2: Viable Options"[1] :
MTGs Mark Rosewater defends the intentional inclusion of bad cards for design reasons, but really it's entirely marketing driven. Their business is to put a collectable barrier between you and the the cards you want so as to sell more packs of those cards. That means mountains of chaff cards are inventible. I think even one single chaff card is a problem that would ideally be fixed, but Rosewater claims that bad cards are ok because they:
a) allow for interesting experimental mechanics that might end up being bad
b) test valuation skills because if all cards were equally good, thered be less strategy
c) give new players the joy of discovering that certain cards are bad, as a stepping stone to learning the game
d) are necessary because even if they came out with a set that consisted entirely of known good cards from old sets, thered still be only 8 tournament viable decks and the rest of the cards would not be used.
The solution to this problem is clear if we only cared about design and not rip-off marketing: print fewer cards. Reason a) is a great one, experimental cards that end up accidentally bad are fine. Reasons b) and c) are just silly. Saying the game would not have enough strategy if bad cards were removed is an insult to Marks own game. Saying that new players need to discover the intentionally bad cards is even more silly because this comes at the cost of making sets overwhelming to new players and needlessly unwieldy for expert players. We all know the real reasoning here is to make players buy more random packs of cards to get at the few good ones.
Finally, reason d) is a blatant admission that the game should have fewer cards. Ironically, Im not even sure d) is true. Maybe printing a large set of all good cards really would lead to more viable tournament decks than the game currently supports. If not though, they should stop printing all that chaff.
I highly recommend reading the entirety of Sirlin's blog posts[2] about balance design, because he comes from a mostly fighting based and some CCG experience, the former genre where balance is extremely hard and important to tackle.
The point ultimately is that from a pure design and balance standpoint, the developers should have fewer cards, and Hearthstone should have fewer well balanced cards. That is not their business model because their business model revolves around getting players to buy card packs. The game should look closer to Killer Instinct with the sparse but very well balanced and fun characters rather than say Marvel vs Capcom or Street Fighter's earlier titles with nearly 50+ characters.
I admire Mark Rosewater and read through nearly all of his excellent five star articles "Making Magic" series[3] but even I see through the ruse - bad cards are designed to get you to search for the 'rarer' cards which get you to buy more cards.
Now there's nothing really wrong with this system honestly, as long as people are perfectly clear on the relationship, but don't defend 'designing bad cards' as a 'design goal', when really is financially driven. Arguing otherwise just confuses your expectations and everyone else's expectations.
This is further compounded by Hearthstone's problem as a purely Digital Card game. Ultimately, you don't own any of the cards in the game. You don't get to take them home with you, and use them like you see fit, unlike in Magic where you get a physical copy. If you get banned from Hearthstone, you lose all the cards. Everything is on the system. You simply pay a 'psuedo rent' to use parts of the system.
Hearthstone is a video game that happens to have cards in it - or units which you buy in order to play the game. Treat it as such. Value it as such.
In order for Hearthstone to improve in this aspect they need:
1) To embrace restricted formats like Magic - because it just becomes an impossible challenge to balance a 1000+ cards in a competitive format.
2) Create far more ways to play with the cards. Current philosophy seems to be that you need to have the right cards to have fun, when the philosophy of the dev team should be having any cards allow you to have fun. Tavern Brawl is an excellent small step, but there needs to be so much more, including custom ladders for a start.
However, even now Hearthstone is STILL in its infancy. Death Knight and Monk haven't even been released yet, and Hearthstone still have under 1000 cards, in addition to many mechanics unexplored. Give it time, and this should sort itself out.
Hopefully.