WHY ARE THERE "BAD/UNPLAYABLE CARDS" IN MAGIC: THE GATHERING?

The reference of this article came from Mark Rosewater, and he made the post more than twelve years ago. And yet it's still very much relevant for our rants and raves about the game, generally, and our booster pulls, specifically. So, why is it that Squire is part of the time-shifted cards in Time Spiral, along with goodies such as Akroma, Angel of Wrath? Why didn't I pull a Flooded Strand instead of Avalanche Tusker? Here what MaRo had to say about the issue:

1. ALL THE CARDS CANNOT  BE GOOD

Power, even in Magic: The Gathering, is relative. Lightning Bolt is only considered as the best burn spell out there because there is no zero mana 3-damange instant burn spell, nor is there a one mana burn spell that lashes out four damage immediately. Additionally, if every card in a set was great, it would make the next set either really weak (which will lessen demand) or either really strong (which would shake up the power creep), and so the best thing to do is allocate these "good" cards among the sets in Standard.

Lightning Bolt Textless Foil
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2. DIFFERENT CARDS APPEAL TO DIFFERENT PLAYERS

However, what happens to the remaining "bad" cards appearing in the set that will not be used as much in competitive play? Well, this is why Magic has different formats. Some cards will find their way in Modern, Vintage, or Legacy. Moreover, sealed and draft games kinda force players to use all the cards. Even now, legendary cards that are not seeing play in Standard will be much sought after by EDH players.
Scapeshift Modern Deck
Scapeshift is now $20 each because of its popularity in Modern <image source>
3. DIVERSITY OF CARD POWERS IS KEY TO DISCOVERY

What makes Magic: The Gathering and other trading card games great is that players get to look at the card and, overtime, get better at determining its short-term and long-term potential. People might say that cards should all be good because people can immediately understand the game, but the research and development division of MTG takes the fact that the average player is about 13 years old (at the time of writing) seriously. Without easy cards to understand, there would be no advanced field for other players to enjoy. Moreover, these beginners will eventually get better and move with the good cards.
Elvish Vanguard Onslaught
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4. POWER LEVELS ARE RELATIVE

MTG intentionally contains cards that are rather difficult to analyze in terms of potential. MaRo noted that this was the case with Lion's Eye Diamond back in the days of Urza's Sage being part of Standard. A card might lose value one day, and become a key card the next.

Lion's Eye Diamond Standard

5. DIVERSITY OF POWER REWARDS THE MORE SKILLED PLAYER

The diversity of cards in terms of power helps make strategic plays an advantage. Being skilled in the game helps you decide which card is bad and which is good. If all cards in a set were good, the beginner or the unskilled player will still play fine because all he/she will get are good cards, and the skilled player's strategic plays will not be as helpful. Bad cards help reward the good players by allowing them to decide properly.

Thragtusk MTG

6. PEOPLE LIKE FINDING HIDDEN GEMS

This is probably one of the reasons I highly agree with. This is why we have the term "sleepers", cards that are seemingly bad or average but are actually great, and Tarmogoyf is definitely the biggest sleeper there is. I am still bitter about this card, as I was interested in having this when FS was released, but was with my grandparents for a month, far far away from the MTG store. Oh well.

Tarmogoyf Future Sight
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7. R&D IS ONLY HUMAN

The Magic R&D department is really cool, I think. But that doesn't mean they are perfect, nor are they all omniscient to determine how the cards they design will affect competitive tournaments. No amount of playtesting by them can really determine which cards will actually be good or bad.

Goblin Rabblemaster Sleeper
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In summary, as MaRo stated:

1. By definition, some cards have to exist. (The most important reason.)
2. Some cards are "bad" because they aren't meant for you.
3. Some cards are "bad" because they're designed for a less advanced player.
4. Some cards are "bad" because the right deck for them doesn't exist yet.
5. "Bad" cards reward the more skilled player.
6. Some players enjoy discovering good "bad" cards.
7. Some "bad" cards are simply R&D goofing up.

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