What do quants actually do?

Could you please elaborate on the responsibilities and tasks that quants typically undertake? I'm quite curious to know more about their role in the realm of finance and cryptocurrency. Could you describe the kind of analytical work they do, the types of models they develop, and how their expertise contributes to decision-making in this field? Also, could you share any insights into the skills and qualifications that are typically required to become a successful quant? Thank you for your insights.