My simple answer to this is, before you consider using a cryptocurrency or a cryptocurrency application long-term, make sure it's
1.  Well decentralized,
2. Transparent
3. Immutable,
4. Censorship resistant,
5. Trustless/permissionless,
6. Privacy-friendly/anonymity-friendly,
7. Secure/safe
8. Consensus-driven... and you can participate in full network consensus without needing to buy stakes/hardware you can't afford.
Consensus should be based on fair merit/reputation system!

Others
9.   It's very useful,
10. its native coin is deflationary,
11. It fairly easy to run full nodes... and allows you to fully control your coin and data.
12. It has to have clear rules/principles/boundaries that shouldn't be crossed for the sake of  proper network decentralization and participants safety.
13. It's unique
Etc.