Mont Blanc has the highest fatality rate of any mountain in Europe. But it’s not because it is a highly difficult mountain to climb which requires a lot of previous experience and climbing skills. It is because tons of people attempt it each year. And out of those people who do, a lot of them are inexperienced or even novice mountain climbers. They are not ready for the most basic mountaineering challenges.
That’s why many of them perish. They are relying on being lucky because they do neither know the mountain nor are skilled enough in winter mountain climbing. That’s why a guide beside you is so valuable, it significantly lowers the chances of a dangerous situation arising.