We know in in Bitcoin ,the miners gets an economic incentive i.e rewards for mining and verifying the transaction to the mainnet. But in case of testnet, there is no real rewards the miners or validators gets in case of Ethereum blockchain. Then why do they perform the computation if they are not incentivised on mining/validating on these testnets. ?
1 Answer
A lot of people who run faucets and testnet validators/miners are doing so out of the goodness in their hearts as opposed to any monetary incentive.
Testnets are a crucial part of creating smart contracts, without them the industry would definitely experience even more exploits than we currently do. So if creating and hosting testnet tools are directly linked to the growth of the industry, it's easy to see why many people are involved in them, despite not being directly financially rewarded.
Anyone who benefits from blockchain growth as a whole, also benefits from testnets since they are an essential stepping stone in Contract creation.
There are also developers building on testnets solely for educational reasons so that they can understand and get more comfortable with the process before taking the next step to mainnet.