This summary is not the rule. The rule text controls.
If someone has the right to enforce an obligation (like collecting a debt or pursuing a legal claim) and they die, that right doesn't just disappear. It passes on to their estate and gets inherited by their heirs or the people who receive their general property under a will. These are called "universal legatees" or "legatees under a universal title," which just means people who inherit the estate broadly rather than one specific item.
If someone left a specific item to a particular person in their will (called a "legacy under a particular title"), that person only gets the right to enforce an obligation if it's directly connected to that specific item. For example, if someone willed a piece of land to their nephew, and there was a legal claim about that land, the nephew could inherit that claim. But they wouldn't automatically inherit unrelated claims that had nothing to do with the land they received.
This same rule applies even if the original person died before they ever filed a lawsuit or took legal action. In other words, you don't lose the right to pursue a claim just because the person who originally had that right passed away before taking action. The right still transfers to whoever properly inherits it, following the same rules described above.