Only invest what you can afford to lose - perspective

So there is that saying that you should "only invest money that you could afford to lose", or that doesn't hurt losing.

While I would partially agree on that, like not taking a credit to invest into stocks / bitcoin, I still find it difficult to use that phrase.

My problem is that a lot of people buy consumer stuff to have fun for a few hours / days / weeks, until they go on and buy the next useless crap to feel better. Everytime they pay money for it and I would say in many cases they will never get back the money they spent. So it seems that buying useless crap and overexpensive consumer stuff is no problem in our society. But in terms of investing people are afraid of losing money lol. Isn't that the pure hypocrisy ?

Its like, people buying stuff for thousands of dollars per year. The Items will just lay arround after some time and will not be used anymore, but investing some amount of money is too dangerous because there IS a chance that the investment could go to zero.

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