Why is this the answer?

The answer is heart because this clever riddle is actually talking about two different ideas of what a heart is: the one that beats in your chest, and the one that holds your feelings. The first line says, "If you break me, I do not stop working." A lot of people talk about having a "broken heart" when they are feeling very, very sad, maybe after saying goodbye to a dear friend or a pet. This makes you feel heartbroken inside. But even when you are sad, your body's heart does not stop doing its job. It keeps right on beating and pumping blood to every part of you, keeping you alive and running. That is the first perfect match for the word heart. It is broken in a feelings way, but not in a real way. The second part says, "If you touch me, I may be snared." To be snared means to be caught, kind of like a tiny animal can be caught in a small trap. This is a secret clue about giving your love or trust to someone. When you allow someone to "touch your heart," you might be falling in love or making a strong, deep friendship. You can feel "caught" by those wonderful, strong feelings of love and happiness. The last and most important part is, "If you lose me, nothing will matter." This clue is about your actual, physical heart. Your heart is the engine of your body. It is the main thing that helps you live and breathe. If your real heart were lost or stopped working, you would no longer be alive. If a person is not alive anymore, nothing else in the world, like games, toys, or even the sun and moon, will matter to them. The word heart fits all the tricky clues, showing us that it is powerful both as a muscle and as the center of all our biggest feelings. It is a perfect puzzle with a powerful answer.