I think you are a little bit confuse here let me put you through investing what you can afford to loose is not an investing strategy rather it is an investing advice given to investors both New and old to invest in bitcoin with what they can afford to loose, because there no guarantee that your bitcoin investment will be successful so returns are not guarantee, since nobody knows what will become of bitcoin tomorrow, that is why it's advisable to invest what you can afford to loose in bitcoin.
It is one part of your investment strategy because you need to have something for cooking, here investing.
You can not invest if you don't have investment capital but how you get the investment capital is important. It's more important to know that what you have after you spend money for investment, like whether you have emergency fund, and at least enough fund for your spendings. It's about risk management of your finance in general and your investment capital in specific.
If you invest what you can not afford to lose or invest all money you have, you have bad financial management, terrible risk management, and they are all terrible parts of your investment. With two bad pieces in your investment strategy, you have lower chance to succeed with investment.Bitcoin investment is not gambling where you begin to speculate how much you should afford to lose while betting, such remarks should be made to gamblers and traders. From the inception of Bitcoin, in fact those that invested in Bitcoin and took the risk are today bubbly in their investment growth. Investment with your discretionary income is what should be advocated and not make it sound like investment in Bitcoin is a risky investment that you invest what you can afford to lose, have you ever seen anybody that has invested in Bitcoin and has been patient enough lost his investment? I believe your answer is no.
Invest with an amount that you can afford to lose is only a warning for you to invest with your discretionary (extra funds that you don't care about even if it's missing or wasted) so that you can hodli for long and don't end up in frustration if bitcoin price goes against you. It also sends a risk signal to you so that you can know that bitcoin is not 100% risk free and no guarantee that you will make profit in the long run.
Am not a big fan of that statement when it comes to Bitcoin investment because in my own opinion, the right statement should be invest with an amount you can do away with for a very long time, or are you trying to say that ten years of Bitcoin investment going down the drain will not have any effect on you mentally?
Let's be realistic here, even though it's an amount you can do away with, if you can accumulate Bitcoin for like ten years upward, even as a low coiner, by that time it's a huge amount of money, so their is no way you will say that ten years of investment is an investment you will lose and you wouldn't lose sleep over it.
Trading, gambling and investing are all risky actions and that's why you shouldn't be carried away and over invest with money that you cannot afford to lose so that you don't feel the pain in regrets.
Gambling and trading has the same level of risk, so i don't think it's proper to compare it to Bitcoin investment that the risk is way below gambling and trading.