Not just to make each race last 10 minutes, but to also make sure it scales with the processing power available. This keeps the transaction history secure beca

Not just to make each race last 10 minutes, but to also make sure it scales with the processing power available. This keeps the transaction history secure because you would need to control immensely more computing power to try and counterfeit the transactions for every 10 minutes back in the past you try to change.