Trust in its simplest form is defined as when one party (trustor) is willing to rely on the actions of another party (trustee). The trustor is inherently uncertain about the outcome of the other’s actions, and can only rely on historical data to model a likelihood of the trustee acting in a way that the trustor expects. In modern society, humans have developed legal contracts that ensure when a trustee does not act in the way they should, there are repercussions for doing so. This works well for the most part, especially given a good enough judicial system and a method of identifying trustors and trustees.
Up until recently, in order for strangers to transact with each other, trust was required (which included some sort of legal contract orchestrated by a third party that would take a fee from them). Then with the creation of Bitcoin, the world was given access to the first trustless mechanism to transact with strangers across the globe. This was achieved through an incentive mechanism (Proof of Work) that ensured most if not all parties acted in the interest of the entire network.
As the blockchain space evolved, new mechanisms of achieving consensus came to be. One of the most dangerous ones has been the advent of Validators. A validator in a blockchain is a “human element” or third party to whom the network cedes some degree of trust. A validator is incentivised by a network to confirm that an event/transaction has occurred on the network. This approach has been/will be adopted by many chains including interoperability chains like Cosmos, Polkadot and Ark who utilise Delegated-Proof-of-Stake (DPoS) or similar consensus models, where there are a set number of validators.
Ceding trust in a decentralized network is dangerous because there are few if no legal repercussions for those validators if they do not act in the way they are meant too. Decentralized networks must either have methods of establishing legal repercussions (which is very difficult to do in the real world) or must rely on a trustless consensus mechanism.
Block Collider chooses to run its multichain without the use of validators and instead rely on Proof of Distance, which sticks to the philosophy of that of Bitcoin; meaning that it removes the requirement to place trust in a fallible party.