What is the most useful cryptocurrency?

In the ever-evolving landscape of cryptocurrencies, it's no easy feat to pinpoint the "most useful" one. However, I'm curious to delve deeper into this question. When we talk about usefulness, are we referring to its widespread adoption, its technical capabilities, or its potential for growth? Bitcoin, for instance, has become synonymous with cryptocurrencies due to its pioneering nature and robust network. However, its transaction speeds and scalability have been questioned. Ethereum, on the other hand, offers a platform for decentralized applications and smart contracts, opening up a world of possibilities. But which of these factors truly define usefulness? So, my question is: When considering the various aspects of cryptocurrencies, which one do you believe stands out as the most useful, and why? Is it the one that's most widely used, the most technologically advanced, or the one that offers the most potential for growth?