Vitalik Buterin: Fast withdrawals from L2 are more important than decentralization

In a post on X, Ethereum co-founder – Vitalik Buterin – emphasized that reducing the withdrawal time of assets from Layer 2 (L2) to Layer 1 (L1) is even more important than achieving "stage 2 decentralization" of L2. He believes this is a key factor that helps Ethereum L1 maintain its central economic role in the entire ecosystem.

"It's great to see so many major L2 projects have reached phase 1," Buterin wrote, responding to a post stating that all six rollup solutions including Base, Optimism, Unichain, Scroll, Ink, and Kinto have updated to comply with the new requirements of phase 1.

He emphasized: "The next goal we should aim for, in my opinion, is quick withdrawals (<1 hour), through validity proofs (or also known as ZK proofs). I consider this even more important than reaching stage 2."

Challenges when withdrawing assets from L2

Currently, withdrawing assets from L2 to L1 can take up to a week if intermediary services are not used. This not only causes inconvenience for users but also creates pressure to use centralized bridging solutions (bridge), which rely on weaker trust models such as multisig wallets or MPC (multi-party computation) – going against the decentralized spirit of Ethereum.

Buterin explained that, in the past, rollups used optimistic proof because zero-knowledge proof or ZK proof technology was still young and expensive. However, the situation has changed rapidly – ZK proof has now developed strongly, allowing Ethereum-compatible rollups to validate transactions at high speed and with superior safety.

He also mentioned platforms like ethproofs.org that are monitoring the development of ZK proof technologies.

Buterin proposed a transition roadmap with a "2 out of 3" proof system (2-of-3), combining ZK proof, optimistic proof, and a trusted execution environment (TEE). This system will validate withdrawals if there is consensus from two out of the three components.

One remaining technical challenge is the gas cost to submit large ZK proofs to the chain – this will be the final bottleneck to address in order to achieve the goal of fast withdrawals.

Shaping Ethereum into a 12-second payment hub

Buterin's long-term vision does not stop at withdrawing funds in one hour. He believes that with improvements in proof aggregation – combining multiple rollup proofs into one – Ethereum L1 could handle payments for many rollups in each block approximately every 12 seconds.

This will facilitate the movement of native assets between Layer 2s through Layer 1 almost instantly, eliminating the need for centralized bridges or prolonged withdrawal waiting times.

In such an architecture, Ethereum L1 is not only the pillar of security but also becomes the high-speed payment hub for the entire L2 ecosystem. This will reinforce Ethereum's role as an "economic heart" where most assets, protocols, and financial activities are still tied to L1, while the scaling process takes place on the layers above.

Buterin concluded: Fast withdrawals are not just an upgrade to the user experience, but a fundamental transformation in the architecture of Ethereum. As proof systems become increasingly optimized and proof aggregation becomes the standard, Ethereum L1 could evolve into a high-speed financial payment layer, serving the growing L2 network without the need for trust.

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