#Bitcoin can serves these purposes:
* Long-term value retention
* Means of payment
* Speculation on rising price compared to fiat currency
Each purpose has a different target group. And there can be alternative solutions to the problem Bitcoin solves.
Even if you live in a country where inflation is as low as 2 % as intended for the European Union for example, it makes sense to not keep all your money in € currency as that becomes devalued significantly over time. But for long term value retention you could also invest in the stock market and buy an ETF.
If you live in a country where the yearly inflation is as low as 2 % as intended for the European Union and you keep 1000 € for your monthly payments, you currently don’t need Bitcoin as a means of payment. Using the € itself is sufficient. But if you live in a country where the yearly inflation is 50 % you might want to switch to using Bitcoin even for your daily payments!
You will only invest in Bitcoin for speculative reasons if you are relatively wealthy and can risk to loose money in the short term or understand Bitcoin very well and have a long-term horizon.