But it kind of does, since you don't own cash but a portion of a company. As long as that company does well for the next 10 years and doesn't go to shit the "va

But it kind of does, since you don't own cash but a portion of a company. As long as that company does well for the next 10 years and doesn't go to shit the "value" stays the same. 10 shares of Company X are still worth 10 shares of Company X in the future in that case. But the monetary value of those shares will most likely change based on inflation.