You are absolutely right!
All the money I invest in Crypto, is not money that I need but it is money that I was spending on useless stuff. This becomes a larger problem, when you make a decent salary.

When investing, I follow a simple rule: "Reason which got me to invest, is the reason which will get me to sell".
If Invest in a ICO to sell early on during the hype, that is when I will sell it.
If I invest in ICO because I believe the product will solve a problem, then I hodl for a few months to a year and see where the product is going before selling.
If I buy to Hold, then I hodl.

In every investment I make a note of when I will get out and I follow it, regardless if I think I will make more if I wait another month.

I cant say I am saving for retirement, since in a few years the bubble may pop and I lose it all, so its important to have an healthy balance of long and short term investments. Meaning, money you can make in the future and profits you will cash out now.

What I noticed: once you save in Crypto, you will find yourself also saving in Fiat when you cash out on your short term investments.

Oh, and never EVER, EVER day trade. You will lose!