That'll vary from person to person, as it can give insight into how they see themselves and what they expect of relationships, possibly other very different things. After all, someone remaining virgin because they firmly believe it should only happen after marriage is very different from someone who is just too socially awkward. A past trauma could also be a reason, so, again, it's something to better know and understand the person.

There's no way to know until you ask, but to me it might mean that they have quite low self esteem, or the opposite, that they have an inflated view of themselves that no one was good enough for them.

It could also communicate that sex or physical intimacy is not important to them. There's absolutely nothing wrong with that, but it would certainly affect my interest in anything past a platonic friendship with them.