The matchmaking algorithm is the unsung hero that determines exactly who you will face every time you press the 'Battle' button.

Many players believe that matchmaking is intentionally rigged against them, constantly forcing them to fight 'hard counters' after a win streak.
The Elo System Adapted
The algorithm's primary goal is to match you against someone with the exact same—or very similar—trophy count.

If the system matches you perfectly, you should mathematically have a 50% chance of winning every single game you play.
If you are hovering around 50%, you are in the correct arena for your skill level.Queue times increase at the top of the ladder.You will eventually stabilize. The Free-to-Play Dilemma
The standard Elo system works perfectly for chess because all pieces are equal, but tower rush games feature upgradeable cards.

To combat this, developers have implemented secondary checks that look at the player's King Tower level.
Conspiracy TheoryThe TruthForced Loss StreaksThe algorithm does not force losses; you are simply playing tilted against harder opponents because your MMR is inflatedRigged Deck MatchingDevelopers have confirmed repeatedly that the algorithm does not read the contents of your deck when finding an opponent Maintaining Competitive Integrity
This is why all true esports tournaments and competitive challenges utilize the 'Tournament Standard' ruleset.

Trust the math, ignore the conspiracy theories, and focus on improving your own gameplay.