[podgaj]

"to make it almost always increase in value"

To any investor this should be the biggest red flag that you are in a Ponzi/pump and dump scheme. "You can't lose!"

And rather than you are "buying electricity" I would say you are buying used electricity, which is useless.

[matheusmoreira]

It's a deflationary currency. The opposite of "USD always decreases in value because of inflation". Not a red flag at all. Even the idea that it's deflationary is debatable since exchanges now offer loans, a service which effectively creates new bitcoins out of nowhere.

[immibis]

Deflationary currencies cannot be deflationary forever. Think for 5 seconds: if that was true, then the person who sold the pizza for bitcoin will eventually have enough value to buy everything on the planet. So will the person whose CPU was mining to keep the pizza warm. Can there be two planets of value on the planet?

[mavhc]

You're buying electricity, and using it to make the bitcoins.

The red flag is you're buying something that's useless. The cost of a bitcoin may be correct, but doesn't mean it's worth the cost.