A person said to me. If you save $20 a week and put it in...

A person said to me. If you save $20 a week and put it in compound interest in your lifetime you will be a millionaire. I was playing with compuers at the time and did a formula on a spreadsheet where you could alter the amount and the interest rate. It didn't take into account tax.
It worked out about 35 - 40 years. I thought double the amount and halve the time but that is not how compound interest works. The biggest factor is time. At 22 you have time on your side so you should invest rather than gamble. Much more boring and if you look at a graph of compound interest nothing seems to happen for year after year. Then it appears to go exponential at the end.
Hare and the tortoise. Easy to be a hare hard to be a tortoise..