Recently, I’ve been pondering a question: why is blockchain technology so impressive, yet it has never achieved widespread adoption? The answer might lie in the so-called "trilemma."

In simple terms, it’s nearly impossible for a blockchain to excel in three areas at once: decentralization, security, and scalability. Want all three? That’s difficult. Usually, you have to sacrifice one or two.

Let’s first look at the current situation. The Bitcoin network can process about 7 transactions per second, and Ethereum only around 15. In comparison, centralized payment systems like Visa can handle 24k transactions per second. The gap is obvious. This is the scalability problem—if blockchain is to serve billions of users, the current speed is simply not enough.

But the contradiction here is that decentralization and security are core values of blockchain. Decentralization means no single controller, and every participant can verify data. Security requires enough nodes to participate in consensus to prevent cheating. Both require time and computational resources, which results in slower speeds.

What’s the simplest way to speed things up? Reduce the number of participants. But this breaks decentralization and also weakens security—fewer participants mean it’s easier for malicious actors to gather 51% of the computing power to attack the network. This is the core of the trilemma.

The good news is that developers haven’t given up. Sharding technology splits the blockchain into multiple smaller parts, each handling its own transactions; some projects switch from proof of work to proof of stake to reduce computational costs; there are also Layer 2 solutions, like sidechains and state channels, which move some transactions off the main chain. These approaches have their pros and cons, but all aim to break through the limitations of the trilemma.

Honestly, there’s no perfect solution, but these efforts are indeed changing the status quo. If these technological paths continue to evolve, the data processing capacity of blockchain should see a qualitative leap. By then, large-scale Web3 applications might no longer be just a dream.