Providing a source of randomness on-chain is difficult:
1. It is hard to create random events on-chain due to the deterministic nature of EVM environments.
2. If the random number generation comes from a centralised source, malicious actors can manipulate it from the source.
很难在链上提供随机性来源：
1、由于EVM环境的确定性，很难在链上创建随机事件。
2.如果随机数生成来自集中来源，恶意行为者可以从该来源对其进行操作。