Morality as a guide to living
To better understand Objectivist ethics, there's an important distinction that needs to be made between its approach and many other ethical systems. There are two basic approaches to morality. One is limit on one's choices, and the other is a guide to living.
The first view is that morality is a limit on your actions. It sets boundaries for you. Don't murder people. Don't steal from people. Don't lie. Don't cheat. Don't speak unless spoken to. It tells you the kinds of things that are bad to do. But it doesn't provide you with much in the way of guidance picking between the remaining choices.
There are many examples of morality as a limit on actions. Let me go through some.
We've already discussed intrinsic values earlier. Since intrinsic values can't be rationally compared, they don't offer much in the way of guidance. But many of these intrinsic values set limitations on your actions, which is their real function. One of my favorite to discuss is vegetarianism. By elevating animal life to some unconnected value, it basically sets up a rule that tells you to not eat meat. It's not that vegetarians actively go out seeking to improve the lives of animals (some might, but it's not necessary). The intrinsic value there just limits the kinds of things they can do.
Since virtue ethics are often just a set of rules to follow, treating kinds of actions as intrinsic values, the same criticism applies to these. So a man of honor must keep his promises, no matter what. He's limited by not being able to choose to break those promises. Honesty would demand someone to never tell a lie, removing those as options. The point here isn't that cutting off particular options is bad in itself. But if that's all the ethical system does, you're still left without a means of choosing between the remaining options. You cut off some, but you can't prioritize the rest. It's an additional problem in that if you find that you must violate one of these rules, you don't have a means of choosing the least important.
Another example is a morality that is only a partial guide to your actions. For instance, altruism might suggest that if you see someone who needs help, the moral thing is to jump in and help. But it doesn't tell you much else. It doesn't inform you on what kind of pleasures you should pursue, what kind of job, what you should do on your free time, or any number of other choices. So a moral code may provide guidance under specific circumstances, but otherwise leave you without a moral compass.
The Objectivist ethics sees morality as a guide to living your life. The point of it is to provide you with the tools you need to make decisions. To the extent that it can't be used for that, the moral code is defective. When understanding an ethical system, it's important to look at this as a benchmark for the value of that system. Does it provide guidance? Or is it just an obstacle?
At any point, with the Objectivist ethics, you can stop and say "what should I do now?". Because life is your standard, you can think of possibilities that enhance your life. You can pick which is the optimal one, and pursue it. You're not stuck wandering. You don't have to leave it to your whims or your implicit philosophy to decide for you. You're able to think it through and pursue your goals.