They sure do, we try very hard to get as close as we can to what an objectivist would consider ‘true’. But nothing in objectivism states that we will ever know what the objective moral truth is. How many stars are there within 100 million light years outside of the observable universe right now? We don’t know. We can’t know. But there still is a correct answer even though we don’t know it. Just as an astronomer might average the count of stars in a similarly sized region and make an estimate of the correct answer, humans will share ideas of morality and endlessly critique them in hopes of getting a closer approximation of what “moral truth” might be.