Indeed, it doesn't feel easy when you look at the price of BTC because the price continues to rise, but what is certain is that because I put in money that I was ready to lose, which was put into buying BTC, of course it felt very light and definitely without a burden.
I prefer you say investing with a discretionary amount because saying that you invest with an amount you can afford to lose seems to me that you are undecided about the productivity of the asset you are investing on thereby you can reluctantly invest lower amounts in your DCA even if you have enough discretionary amount to boost your investment. Investing with an amount you can afford to lose do not necessarily mean that you should have that mentality that it can be lost especially if you have a long term mindset. It is mostly those with short term plan that worries more about the amount they invested with, even though it is an amount they can afford to lose without having a deep feeling of emotions if actually such scenario turns up in the future. Bitcoin has gone above those days when most people were investing in it with fear of it crashing along the line. However, it is not a prerequisite that you will make profits at every point in your investment in bitcoin but there is need to have that positive mindset while investing at the level of your discretionary income.
I think that the right statement he should have used is investing with an amount of money you can do away without for a very long period of time, because Bitcoin investment is not gambling whereby you gamble with an amount you can afford to lose, truly long are those days when investors are investing with fear that Bitcoin will not be worth it, but as of today, even haters of Bitcoin knows that it's steadily on the rise, it's just a matter of time, so it's best to use the statement of investing an amount you can do away with for a very long time, than to say invest with an amount you are willing to lose.
The statement is okay, and there's nothing wrong with it. Bitcoin investment is a long-term investment before an investor can fully get the profit that can possibly give him or her financial freedom, so it is always right to tell someone who is willing to invest in bitcoin to use the money he or she can possibly afford to lose so that he or she will use it as a guide and invest with the money he or she can possibly afford to lose; in case something bad happens along the line, he or she will not find it difficult to solve his or her daily expenses. We all know nothing will happen to bitcoin, but it is always advisable to invest with the money you can possibly afford to lose.