Even after earning $1000 and living a good life, he must plan for his future and when he plans for his future, he can invest part of his income if he wants. Investing doesn't depend on how much money you are earning every month, basically investing depends on the individual. If the person wants to invest then he can invest even earning a relatively small amount of money. You have contradicted me by saying that it is easy to think about something but difficult to act on it, to which I will tell you that if you have a sincere desire you can do anything.
when it come to investing in bitcoin it depends on one financial capability in his process of accumulating. For instance an average man is being paid $500 monthly, the guy can decide to fixed his DCA purchasing monthly by buying $100 worth of bitcoin monthly. While using his remains to coverup some expenses and flow with his regular life style . Because if such individuals decided to put more percentage of his earning in his investment without having more income to sustain him, like using $400 to accumulate while keeping $100 as emergency funds. Such individual would endup tampering with his investment for survival. So I will say the rate of one accumulating Bitcoin is directly proportional to his sources or earnings. Sometime as an investor one should be flexible, if by any chances such users endup having extra cash to spare, without it coming from his monthly salary. Let me say such individual found that he have extra funds to spare like $200 without touching his monthly salary he may decide to add that money ($200) to his normal DCA money which is $100 making it $300 he's going to use to purchase Bitcoin ( inorder to coverup some Gab in his Accumulation without being too aggressive). that moment, like a form of lump-summing going all in with that spare money and his normal fixed amount fir DCAing, with the other remains of his salary as emergency funds.