Do you think people should hold off on serious romantic relationships until they know themselves well?

Well to be perfectly honest, if you don't even try a relationship, you won't EVER know what you want from one.

Yes, you should have a general idea from the get go. But there are certain aspects of a relationship that you only figure out you want/don't want when you experience them yourself.

It's okay to get into a more serious relationship and learn as you go. You'll break some hearts, and some people will break yours. Breakups are terrible in the short-term, but in the long term they keep two people who can't commit two each other from getting stuck together. BOTH people need to be into the commitment for it to work.

You can know everything about cars in your head, but if you climbed in without practicing first you will kill yourself and several pedestrians. Practice makes perfect.

So have an idea of what you want, then get into the relationship with somebody who appears compatible. Then just BE HONEST with yourself. If it isn't working, accept the failure. Even if they love you to death, they deserve someone who returns that. If you aren't that person, it is even worse to lead them on. The reverse is also true. If they aren't into you, accept the end and find someone who is nuts about you just as much as you are about them.

I wish that it were that simple. Learning by breaking someone's heart is dreadful to say the least. Hold off on any binding commitment until you are sure. If you end up with children, a breakup would be a disaster for the kids.

Sounds perfectionistic to me. It's like saying anyone who makes a mistake in life is irresponsible. Just go through life without making mistakes. WOW! Why didn't I think of that!? I must not be as smart as your friend.

Repeating the same mistake over and over is irresponsible. But not making one, or at least guaranteeing one won't make one, is impossible. Seldom in life are we working with perfect and complete information when making choices. And perfect choices cannot be made with imperfect information.

Any person with high morals would agree with your friend.

How would you ever know when your ready if you did that?