The OP Stack blueprint plan specifies that the Sequencer should be shared, but the Sequencer is a key component for each Layer2 chain to make money and profit. Sharing the Sequencer is tantamount to eating from a big pot? Why eat a big pot of rice, how to eat it, and where are the difficulties?

Why share the Sequencer to eat a big pot?
1) Independent Sequencers have problems of high operation and maintenance costs, high single-point security risks, and excessive centralization. Sharing Sequencers can collectively share operating costs, collectively supervise each other, and collectively govern together, reducing the risk of single-point failures, and Sequencer is a key component for interacting with the main network. A highly shared and highly utilized Sequencer interacts with the main network, avoiding the security consensus risks that exist in the interaction between a bunch of Sequencers and the main network.
2) The role of Sequencer is to submit batch transactions to the main network rollup smart contract, so its composition is usually several EOA addresses, so the private key management and authority sharing of EOA addresses become difficult problems. An organization can be managed with MPC multi-signature, but what about multi-organization sharing? It will definitely involve the governance committee. The private key of each organization must have people from other organizations to take on the multi-signature role, cross-manage the management roles of each organization, and also need a transparent smart contract on-chain accounting mechanism. The contribution of the chain is distributed in a reasonable proportion. This is really a big off-chain socialization project, and the difficulties can be imagined.
3) Shared Sequencer is the key to the share liquidity of each chain and the realization of cross-chain communication. The layer2 multi-chain era imagined by OP Stack is not a closed chain that cannot share liquidity. A shared Sequencer is a relay chain similar to Cosmos IBC, which can participate in the resource coordination, management and deployment of each chain, and can be naturally more Conveniently realize the circulation of assets and information between heterogeneous chains. For example, the A-chain and B-chain of the OP Stack ecology need to conduct flash loan integrated transactions, which can be completed quickly by sharing the Sequencer, without even destroying the atomic transaction attribute. This is the basis for liquidity sharing between drive chains.